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                                                                   Exhibit 10.51

                            FIRST ADDENDUM TO LEASE

     This is an Addendum ("First Addendum") to that certain Lease between
IRRADIO HOLDINGS, LTD., a Florida limited partnership ("Landlord") and SPANISH
BROADCASTING SYSTEM, INC., a Florida corporation ("Tenant"), said Lease dated
______________, 2000 ("Lease"). All defined terms in this First Addendum shall
have the same meaning as in the Lease, except if otherwise noted. Except as
amended and modified by this First Addendum, all of the terms, covenants,
conditions and agreements of the Lease shall remain in full force and effect. It
is the intention of Landlord and Tenant that in case of any conflict between the
terms of the Lease and this First Addendum, this First Addendum shall prevail
and any conflicting language, terms or provisions in the Lease shall be
inoperative. This First Addendum is executed by Landlord and Tenant in
compliance with Section 15.07 of the Lease, to-wit:

A.   FIXED MINIMUM ANNUAL RENT

     Section 2.01(b) is hereby deleted and replaced by the following:

     Beginning in Lease Year Two, the Fixed Minimum Annual Rent shall increase
at the rate of $1.00 per square foot pursuant to the following schedule:

<TABLE>
<CAPTION>
<S>                 <C>                      <C>
Lease Year Two      $31.00 per square foot   $432,543.00 Annually
Lease Year Three    $32.00 per square foot   $446,496.00 Annually
Lease Year Four     $33.00 per square foot   $460,449.00 Annually
Lease Year Five     $34.00 per square foot   $474,402.00 Annually
Lease Year Six      $35.00 per square foot   $488,355.00 Annually
Lease Year Seven    $36.00 per square foot   $502,308.00 Annually
Lease Year Eight    $37.00 per square foot   $516,261.00 Annually
Lease Year Nine     $38.00 per square foot   $530,214.00 Annually
Lease Year Ten      $39.00 per square foot   $544,167.00 Annually
</TABLE>

B.   ADDITIONAL RENT AND OPERATING EXPENSES

     Section 2.02(b) is hereby revised as follows:

     (i) The following is hereby added to the end of Section 2.02(b)(i):
"including the building manager but not above the level of building manager."

     (ii) Section 2.02(b)(xi) is hereby deleted in its entirety and replaced
with the following: "the cost of any capital improvements to the Building or of
any machinery or


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equipment installed in the building which improves the operating efficiency of
the Building and which is made or becomes operational, as the case may be,
after the expiration of the first (1st) lease year, to the extent of such cost,
amortized over the useful life of the improvement, machinery or equipment (as
reasonably estimated by Landlord)."

     (iii)   Section 2.02(b)(xii) is hereby modified to add the following after
the word "legal:" "(to the extent incurred to enforce service contracts with
respect to the Building)."

     SECTION 2.02(c) IS HEREBY REVISED AS FOLLOWS:

     (i)     Section 2.02(c)(ii) is hereby amended and restated in its entirety
as follows: "interest, penalties and charges on and amortization of debt."

     (ii)    The following is hereby added to the end of Section 2.02(c):
"(xiii) rents under any superior lease or other lease and the cost of
consummating any superior lease or other lease, (xiv) the cost of any
installation and decoration incurred in connection with preparing space for any
other tenant of the Building, (xv) all brokerage commissions, (xvi) taxes and
assessments in respect of any air rights or development rights now or hereafter
appurtenant to, or used in connection with the construction of, the Building,
(xvii) costs incurred by Landlord as the result of a breach by Landlord of a
lease or other occupancy agreement covering space in the Building, (xviii) the
cost of installing, operating and maintaining any commercial concessions (other
than the garage) operated by Landlord in the Building or of installing,
operating and maintaining any specialty services, such as a Building cafeteria
or dining facility, or an athletic, luncheon or recreational club, (xix) all
additions to Building reserves, (xx) dues paid to trade associations and
similar expenses if there is no resulting benefit to the Building, (xxi) the
cost of removing Hazardous Substances in order to comply with Environmental
Laws, (xxii) the cost of preparing tax returns and financial statements,
(xxiii) the expense of operating and maintaining space outside the Building
used for management purposes, and (xxiv) the cost of curing any condition
existing on the date hereof which is a violation of any Requirement or
insurance requirement existing on the date hereof (other than the annual
expenses to fund the Building compliance plan with respect to the American With
Disabilities Act.)"

      SECTION 2.02(d) IS HEREBY REVISED AS FOLLOWS:

      (i)    Section 2.02(d)(ii) is hereby amended to insert the word
"reasonable" between the words "any" and "expenses".

      (ii)   The following is hereby inserted following the second complete
sentence of Section 2.02(d): "The amount of any assessment included in Taxes
shall, if payable in installments, be limited to the amount of the installment
due in respect of the applicable Tax Year, together with any interest payable
in connection therewith (other than interest payable by reason of the
delinquent payment of such installment). All income, estate, succession,
inheritance, transfer and franchise taxes shall be excluded from Taxes."

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      (iii)  The last complete sentence of Section 2.02(d) is hereby amended
and restated in its entirety as follows: "To the extent that Landlord receives
a tax refund, thereby reducing the Operating Expenses for a year in which an
increase in Operating Expenses has been paid by Tenant, Tenant's proportionate
share of such refund (not to exceed the Operating Expenses paid by Tenant)
shall be applied against the next Fixed Minimum Annual Rent payments becoming
due under the Lease, or if such refund is received by Landlord after the Term
of this Lease (and any renewal term), Tenant's proportionate share of such
refund (not to exceed the Operating Expenses paid by Tenant) shall be promptly
refunded to Tenant. The foregoing provisions shall survive the expiration of
this Lease.

C.  COMMON USE AREAS AND FACILITIES

    SECTION 3.01 IS HEREBY REVISED AS FOLLOWS:

    The following is hereby added to the end of Section 3.01: "Notwithstanding
the foregoing, in no event shall the exercise of Landlord's rights under this
Section unreasonably interfere with the conduct of Tenant's business in the
Leased Premises, nor shall they materially impair access to the Leased
Premises."

    SECTION 3.02 IS HEREBY REVISED AS FOLLOWS:

    The following is hereby added to the end of Section 3.02: "Notwithstanding
the foregoing, Landlord agrees that provided Tenant is not in default hereunder
beyond all applicable notice and cure periods, no such license shall be revoked
if such revocation would serve to unreasonably interfere with the conduct of
Tenant's business in the Leased Premises, nor shall they materially impair
access to the Leased Premises."

D.  SERVICES

    SECTION 4.01 IS HEREBY REVISED AS FOLLOWS:

      (i)   The third sentence of the fifth full paragraph (next to last) is
hereby amended to insert the word "reasonably" between the words "that" and
"considered."

      (ii)  The following is hereby inserted after the word "Lease" in the
second line of the last full paragraph of Section 4.01: "beyond all applicable
notice and grace periods,"

      (iii) The following is hereby added to the end of the last full paragraph
of Section 4.01: "Notwithstanding the foregoing, in the event the failure to
provide any such service or services renders the Leased Premises untenantable
for the conduct of Tenant's business at the Leased Premises as reasonably
determined by Landlord for a period in excess of 10 consecutive business days
and Landlord has not commenced to cure such failure or is otherwise not
proceeding with due diligence to cure such failure, Tenant shall have the right
to a rent abatement for the period of time following such 10 business day
period until the Leased

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Premises is rendered tenantable."

     SECTION 4.02 IS HEREBY REVISED AS FOLLOWS:

             The last sentence of Section 4.02 is hereby amended to insert the
following after the word "unreasonable:" "(and shall be at least Tenant's
Proportionate Share of such space)."

E.   USE

     ARTICLE V IS HEREBY REVISED AS FOLLOWS:

             The following is hereby inserted after the word "office" in the
first sentence: "(and legally permitted ancillary uses)."

F.   INSURANCE AND INDEMNITY

     SECTION 6.05 IS HEREBY REVISED AS FOLLOWS:

             The following is hereby inserted at the end of the first sentence
of Section 6.05: "except to the extent arising from the gross negligence or
wrongful act of Landlord and Landlord's agents, contractors or employees."

     A NEW SECTION 6.07 IS HEREBY ADDED AS FOLLOWS:

             Section 6.07 Landlord's Insurance.

             Landlord shall maintain, at all times during the Term:

              (a)  comprehensive general public liability insurance covering (i)
                   Landlord's liability with respect to any construction that
                   Landlord may perform in connection with the Building and (ii)
                   Landlord's liability for death, bodily injury or property
                   damage occurring in, on or about the Building, including
                   liability arising from any act or omission by Landlord or its
                   agent relating to the public portions of the Building. Such
                   insurance shall have a combined limit of not less than
                   $5,000,000 in respect of bodily injury, death or property
                   damage in any one occurrence. Such limit shall be increased
                   from time to time (but without obligation to do so more than
                   once every 5 years) so as to be consistent with the limits
                   for such insurance which is customarily carried by owners of
                   similar buildings in Miami, Florida. Such liability coverage
                   shall include a contractual liability endorsement with
                   respect to this Lease; and

              (b)   "all risk" property insurance covering the Building (but not
                    including any Tenant Improvements) in an amount which is
                    required by any mortgagee

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               holding a mortgage encumbering the Building, or, to the extent
               not required by any such mortgagee, in an amount reasonably and
               customarily carried by owners of properties similar to the
               Building in Miami.

G.   DESTRUCTION AND CONDEMNATION

     Section 7.01(b) is hereby revised as follows:

          The words "casualty loss" in the first line are hereby replaced with
"Casualty Loss."

     Section 7.01(c) is hereby revised as follows:

          Section 7.01(c) is hereby amended and restated in its entirety as
follows: "In the event of a Casualty Loss to the Leased premises which Casualty
Loss does not render the Leased Premises untenantable for the operation of
Tenant's business, there shall be no rent abatement and the Landlord shall
repair the Leased Premises and restore the Leasehold Improvements to their
Original Condition, all within 180 days of the occurrence of the Casualty Loss."

     Section 7.01(d) is hereby revised as follows:

          (i)  The following is hereby inserted in the second line of Section
7.01(d) after the word "untenable": "for the operation of Tenant's business, as
reasonably determined by Landlord"

          (ii) Section 7.01(d) as hereby amended and restated as follows: "In
the event of a Casualty Loss to the Leased Premises which Casualty Loss does not
render more than fifty percent (50%) of the Building untenantable, as reasonably
determined by Landlord, provided (i) the Building may be repaired to its
Original Condition within eighteen (18) months from the date of the occurrence
of the Casualty Loss, and (ii) Landlord's mortgagee makes the insurance proceeds
available to Landlord, Landlord shall restore the Premises to its Original
Condition within eighteen (18) months of the date of the occurrence of the
Casualty Loss and Tenant shall receive an abatement of rent in proportion to
that part of the Leased Premises which is untenantable for the operation of
Tenant's business as reasonably determined by Landlord retroactive to the date
of such Casualty Loss until the Leased Premises are restored."

     Section 7.01(e) is hereby amended as follows:

          The first paragraph of Section 7.01(e) is hereby amended and restated
as follows: "In the event of a Casualty Loss to the Leased Premises (i) which
Casualty Loss renders more than fifty percent (50%) of the Building
untenantable, as reasonably determined by Landlord, (ii) which results in damage
to the Building which cannot be restored to its Original Condition within
eighteen (18) months following the date of the occurrence of the Casualty Loss,
or (iii) and the Landlord's mortgagee does not make the insurance proceeds
available to the Landlord


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Landlord shall have the following options, one of which must be exercised by
delivery of notice to Tenant no later than 180 days from the occurrence of the
Casualty Loss:"

     SECTION 7.01(e) IS HEREBY REVISED AS FOLLOWS:

          The following is hereby inserted in the first line of Section 7.01(e)
after the Word "untenable": "for the operation of Tenant's business, as
reasonably determined by Landlord"

     SECTION 7.01(g) IS HEREBY REVISED AS FOLLOWS:

          The following is hereby inserted at the beginning of Section 7.01(g):
"Subject to Landlord's obligation to maintain the insurance required under
Section 6.07 of this Lease,"

H.  DEFAULTS AND REMEDIES

     SECTION 8.01 IS HEREBY REVISED AS FOLLOWS:

          (i)   Section  8.01(c) is hereby amended and restated in its entirety
as follows: "Failure of Tenant to pay any installment of Fixed Minimum Annual
Rent or Additional Rent ("Rent") due hereunder, or any other sum herein
required to be paid by Tenant which is not paid within five (5) days following
notice of demand for payment from Landlord; provided, however, that Tenant
shall not be entitled to receive notice more than twice in any one Lease Year,
and after the second notice is given in any one Lease Year, the aforestated
five (5) day grace period shall be calculated from the date payment is
otherwise due under this Lease."

          (ii)  Section 8.02(d) is hereby amended to replace "ten (10)" in the
first and second lines thereof with "thirty (30)"; and to replace "thirty (30)"
in the last line thereof with "sixty (60)."

          (iii) Section 8.01(f) is hereby deleted in its entirety.

          (iv)  Section 8.01(g) is hereby deleted in its entirety.

     SECTION 8.03 IS HEREBY REVISED AS FOLLOWS:

          The following is hereby added to the end of Section 8.03:
"Notwithstanding the foregoing, provided Tenant is not in default under this
Lease, Landlord agrees that the foregoing lien shall be automatically
subordinate to any lien held by an institutional lender or vendor providing
financing for leasehold improvements (which do not constitute fixtures),
furniture, trade fixtures, equipment and/or other personal property of Tenant
or a corporate institutional lender of Tenant who requires a lien on all of the
Tenant's assets."

     SECTION 8.07 IS HEREBY REVISED AS FOLLOWS:

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          The second full sentence in Section 8.07 is hereby deleted in its
entirety.

     SECTION 8.08 IS HEREBY REVISED AS FOLLOWS:

          The reference to "eighteen percent (18%)" in the second line of
Section 8.08 is hereby replaced with "four (4) percentage points over the then
applicable "Prime Rate" as published in the Wall Street Journal."

     SECTION 8.09 IS HEREBY REVISED AS FOLLOWS:

          The reference to "twice" in the fifth line of Section 8.09 is hereby
replaced with "one and a half."

I.   ALTERATIONS

          (i)   The following is hereby inserted before the word "alterations"
in the first line of Article IX: "structural or material."

          (ii)  The following is hereby inserted following the first sentence
of Article IX: "The foregoing shall not be deemed to limit in any way Tenant's
rights to perform any non-structural or cosmetic alterations to the Leased
Premises, provided the same do not require a building permit."

          (iii) The following is hereby inserted at the end of the first
paragraph of Article IX: "Landlord shall inform Tenant in writing at the time
of the approval of any Alteration whether Landlord will require the removal of
such Alteration at the end of the Term. In the event Landlord fails to give
such notice or notifies Tenant that such Alteration need not be removed, then
Tenant shall have no obligation to remove said Alteration at the end of the
Term."

J.   TRADE FIXTURES

          The following is hereby deleted from the first sentence in Article X:
"shall be new or completely reconditioned and"

K.   QUIET ENJOYMENT

          Article XI is hereby amended and restated in its entirety as follows:
"Provided that the Tenant is not in default beyond all applicable notice and
cure periods under the Lease and the Lease otherwise remains in full force and
effect. Tenant shall peaceably and quietly hold and enjoy the Leased Premises
for the Term hereby demised without hindrance or interruption by Landlord or
any other person or persons lawfully or equitably claiming by, through or under
Landlord, subject, nevertheless to the terms and conditions of this Lease."


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L.   MAINTENANCE

     The first sentence of Article XII is hereby amended and restated as
follows: "Tenant shall, at all times, keep the Leased Premises (including
maintenance of its entrances and all glass) and all interior partitions, doors,
fixtures and equipment in good order, condition and repair, except for the
structural portions of the Building and the lighting (including replacement of
standard lamps and bulbs), heating, plumbing fixtures, air conditioning system
and other mechanical systems and common areas in and about the Building, which
shall be maintained by Landlord."

M.   MISCELLANEOUS

     SECTION 15.03 IS HEREBY REVISED AS FOLLOWS:

          (i)   The following is hereby inserted following the words "Landlord
may" in the third line of Section 15.03: "reasonably." The words "or desirable"
are hereby deleted in the third line of Section 15.03 and are hereby replaced
with "or as may be otherwise permitted or required to be made under this Lease,"

          (ii)  The following is hereby inserted prior to the words "the Fixed
Minimum Annual Rent" in the third line of Section 15.03: "except as set forth
below."

          (iii) The following is hereby added to the end of Section 15.03:
"Notwithstanding the foregoing, if any such work by Landlord materially and
adversely interferes with Tenant's use and occupancy of the Leased Premises or
Tenant's access such that more than twenty five percent (25%) of the Leased
Premises shall be untenantable or inaccessible and is not able to be used by
Tenant for the conduct of its business for more than ten (10) consecutive
business days, Tenant shall receive an abatement of the fixed rent and
additional rent allocable to such untenantable or inaccessible portion of the
Leased Premises, for the period of such untenantability or inaccessibility
following such ten (10) business day period."

     SECTION 15.04 IS HEREBY REVISED AS FOLLOWS:

          The following is hereby added to the end of Section 15.04(a):
"Notwithstanding the foregoing, (i) the transfer of up to 49% of the outstanding
stock of Tenant or the transfer of shares of the Tenant that are publicly traded
on a recognized stock exchange shall not constitute an assignment under this
Lease, (ii) the Tenant may assign this Lease without Landlord's consent to any
entity controlling, controlled by or under common control with Tenant, provided
that no such assignment shall relieve Tenant from any liability under this
Lease, whether accrued to the date of such assignment or thereafter accruing,
and provided further that such assignee assumes, in writing, all of Tenant's
obligations under the Lease, in form and content reasonably acceptable to
Landlord, and (iii) the Tenant my assign this Lease without Landlord's consent
to a successor entity in connection with a merger or sale of the entire business
of Tenant provided (x) such successor entity has a net worth equal to or greater
than the net worth of the Tenant as of the date



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of such assignment, (y) that no such assignment shall relieve Tenant from any
liability under this Lease, whether accrued to the date of such assignment or
thereafter accruing, and (z) that such assignee assumes, in writing, all of
Tenant's obligations under the Lease, in form and content reasonably acceptable
to Landlord."

     SECTION 15.05 IS HEREBY REVISED AS FOLLOWS:

     A new section 15.05(d) is hereby added as follows: "Landlord shall obtain a
non-disturbance agreement in favor of Tenant from its existing mortgagee on such
mortgagee's customary form, and Tenant shall execute such form to evidence the
subordination of the Lease and attornment to the mortgagee. With respect to
any future mortgagee's, Landlord shall use its best efforts to obtain a
non-disturbance agreement in favor of Tenant from its mortgagee on such
mortgagee's customary form and Tenant shall execute such form to evidence the
subordination of the Lease and attornment to the mortgagee. Notwithstanding
anything herein to the contrary, the subordination of this Lease to any
particular mortgage granted by Landlord on the Leased Premises and/or the
Building shall be subject to and conditioned on Tenant's receipt of a
non-disturbance agreement from the particular mortgagee as provided above."

     SECTION 15.16 IS HEREBY REVISED AS FOLLOWS:

     Section 15.16 is hereby amended and restated in its entirety as follows:
"Taking possession of the Leased Premises by Tenant shall be conclusive evidence
as against Tenant that (other than latent defects) the Leased Premises were in
good and satisfactory condition when possession was so taken."

     SECTION 15.20 IS HEREBY DELETED IN ITS ENTIRETY.

     SECTION 15.22 IS HEREBY REVISED AS FOLLOWS:

     The following is hereby inserted at the end of Section 15.22: "other than
products (e.g. cleaning products and copier toner) customarily used in premises
similar to the Leased Premises which are used in compliance with all applicable
laws."

     SECTION 15.24 IS HEREBY REVISED AS FOLLOWS:

     The following is hereby added to the end of Section 15.24: "Provided Tenant
requests such certificate for a legitimate business purpose, Landlord shall be
obligated to deliver to Tenant the estoppel certificate information required
herein of Tenant within the time periods required of Tenant upon written request
therefor."

     SECTION 15.25 IS HEREBY REVISED AS FOLLOWS:

     The following is hereby inserted after 15.25(d): "or (c) apply the Rules or
Regulations in a discriminatory manner."




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     SECTION 15.26 IS HEREBY DELETED IN ITS ENTIRETY.

M.   RULES AND REGULATIONS

     RULE 1 IS HEREBY REVISED AS FOLLOWS:

     The following is hereby add to the end of the first sentence in rule 1:
"which will not be unreasonably withheld or delayed."

     RULE 4 IS HEREBY REVISED AS FOLLOWS:

     The following is hereby inserted at the beginning of rule 4: "Except as
set forth in the Lease,"

     RULE 16 IS HEREBY REVISED AS FOLLOWS:

     The following is hereby inserted before the word "opinion" in rule 16:
"reasonable."

N.   OPTION TO RENEW

          THE FOLLOWING IS HEREBY ADDED TO THE LEASE:

               Provided Tenant has complied with all the terms and conditions
          of the Lease and is not in default or breach of its obligations
          thereunder, Landlord grants to Tenant the option to renew the term
          of the Lease for two additional (5) year periods ("Renewal Term(s)")
          to commence at the end of the Lease Term or Renewal Term. Tenant must
          exercise its option to renew by delivering written notice of such
          election to Landlord at its place of business at least One Hundred
          Eighty (180) days prior to the expiration of the current Lease Term or
          the First Renewal Term, as the case may be. The terms and conditions
          of the Renewal Term shall be on the same terms set forth in the Lease
          except that all rent, including but not limited to, all Additional
          Rent and other charges payable during the Lease Term shall be at the
          then current prevailing market rate (the "Prevailing Market Rate") at
          the time the applicable Renewal Term commences and there shall be no
          additional Renewal Terms other than those provided above. Prevailing
          Market Rate shall be computed as of the date in question with
          consideration being given to then-current annual basic rental charges
          and other additional rent for new leases then currently, or within
          the preceding twelve (12) month period, being or that have been
          negotiated or executed in comparable space located in the Building,
          or if no new leases are then currently, or within the preceding twelve
          (12) month period, being or that have been negotiated or executed
          then the comparison shall be made based on comparable space located
          elsewhere in first-class office buildings comparably aged and equipped
          located in Coconut Grove

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or, if no comparables are available, in Miami's Central Business District.

     Notwithstanding anything to the contrary herein contained, the parties
hereby agree that, at the time Landlord gives its initial determination of any
Prevailing Market Rate, Landlord shall have the right, exercisable by written
notice to Tenant: (i) to change the base taxes to an amount equal to the actual
amount of taxes for the immediately preceding tax year for which Landlord has
actual tax data, and (ii) to change base operating expenses and/or building
energy utility cost base from the respective amounts to an amount or amounts, as
the case may be, equal to the actual amount of operating expenses and/or the
actual amount of building energy/utility costs, as the case may be, for the
immediately preceding operating year. In determining Prevailing Market Rate, the
amount of base taxes, base operating expenses and/or building energy utility
cost base and electricity shall be taken into account and given effect.

     Landlord shall initially designate a Prevailing Market Rate and shall
furnish data in support of such designation to Tenant (the "Landlord's
Designated Amount"). If Tenant disagrees with Landlord's Designated Amount, then
Tenant shall have the right by written notice given within thirty (30) days
after Tenant has been notified of Landlord's Designated Amount, to submit to
Landlord the amount that Tenant considers to be the Prevailing Market Rate,
together with data in support thereof (the "Tenant's Designated Amount").
Thereafter, the parties shall have a period of thirty (30) days to engage in
discussions for purposes of arriving at a mutually acceptable amount. If the
parties are unable to do so, then promptly following the expiration date of such
thirty (30) day period, the parties shall submit Landlord's Designated Amount
and Tenant's Designated Amount to the nearest local office of the American
Arbitration Association (the "Association") so that either Landlord's Designated
Amount or Tenant's Designated Amount is selected as the amount which will
constitute the Prevailing Market Rate under the Lease. In that regard, it is
understood and agreed that no amount other than the Landlord's Designated Amount
or the Tenant's Designated Amount may be selected by the Association. Each party
shall equally share the costs of arbitration hereunder. The decision of the
Association shall be binding on the parties and shall be incorporated into the
terms of the Lease. In the event the matter is submitted to the Association for
resolution, then during the pendency of the dispute, Tenant shall pay rent under
the Lease to the Landlord in an amount equal to Tenant's Designated Amount (the
"Tenant's Rent Payment") and Tenant shall pay the difference, on the same due
date as the rent is due under the Lease, between Tenant's Designated Amount and
Landlord's Designated Amount into the trust account of Tenant's counsel ("Escrow
Agent") to be held pending resolution of the dispute.

     Upon resolution of the dispute and determination of the Prevailing Market
Rate by the Association and in the event the Prevailing Market Rate set by the


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     Association differs from the Tenant's Rent Payment, the Tenant shall pay
     and/or cause Escrow Agent to pay to Landlord any deficiency in unpaid rent
     or Landlord shall pay to Tenant any overpaid rent within five (5) business
     days of the Association's written decision and a failure to pay such amount
     during such time period shall be deemed a default of such party's
     obligations under the Lease. Furthermore, in the event either Landlord or
     Tenant fails to pay 1/2 of the arbitration costs within five (5) business
     days from the earlier of (i) any invoice due date or (ii) any request for
     payment made by the Association or any arbitrator, the same shall be a
     default of that party's obligations under the Lease.

O.   STORAGE SPACE:

          Tenant shall have the right to the use of that certain storage space
     located on the 7th floor of the building's garage hereby designated as
     Storage Space No 12 per the attached plan (Exhibit F) consisting of 911
     rentable square feet at the rate of $10.00 square feet or Seven Hundred
     Fifty Nine and 16/100 Dollars ($759.16) per month plus applicable sales
     tax. Said rate shall increase annually by $0.50 per square foot.

P.   SIGNAGE

          Provided that Tenant is not in default of any term, condition or
     covenant of the Lease beyond all applicable notice and grace periods,
     Tenant shall have the right, at its sole cost and expense, to install
     rooftop signage on the building. Prior to installation, Tenant shall submit
     its proposed signage plans (including design, content, location and
     electrical plans) for Landlord's approval, which may be withheld in
     Landlord's sole and absolute discretion. Said signage must comply with
     Landlord's signage criteria and all relevant municipal codes and
     regulations. Tenant shall be responsible, at Tenant's sole cost and
     expense, for obtaining all permits and approvals required to erect and
     maintain said signage. Additionally, Tenant, at its sole cost and expense,
     shall maintain and remove signage, if necessary. Upon the expiration or
     earlier termination of this Lease, if requested by Landlord, Tenant shall,
     at Tenant's sole cost and expense, remove such signage.


                 [SIGNATURE BLOCK CONTINUED ON FOLLOWING PAGE]


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     IN WITNESS WHEREOF, the parties hereto have executed this First Addendum
as of this 14 day of December, 2000.

/s/ MARIA SHEFFY                  LANDLORD:
-----------------------           IRRADIO HOLDINGS, LTD.
AS TO LANDLORD                    A FLORIDA LIMITED PARTNERSHIP

/s/ KIM TAYLOR                    BY: TERREMARK MANAGEMENT SERVICES,
-----------------------           INC., A FLORIDA CORPORATION,
AS TO LANDLORD                    MANAGING AGENT

                                  BY: /s/ WILLIAM J. BIONDI
                                      ------------------------------
                                      WILLIAM J. BIONDI
                                      PRESIDENT


                                  TENANT:
                                  SPANISH BROADCASTING SYSTEM,
                                  INC., A FLORIDA CORPORATION

/s/ illegible                     /s/ JOSEPH S. GARCIA
-----------------------           ----------------------------------
AS TO TENANT

/s/ illegible
-----------------------
AS TO TENANT



                                       13

<PAGE>   14
                                  EXHIBIT "F"

                                  (Blueprint)

<PAGE>   15
                                  (Blueprint)