Document:

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                                                                     EXHIBIT 4.7

                            LOCK-UP LETTER AGREEMENT

Spanish Broadcasting System, Inc.
2601 South Bayshore Drive
PH II
Coconut Grove, Florida 33133

Dear Sirs:

               Spanish Broadcasting System, Inc. (the "Company"), Rodriguez
Communications Inc. ("RCI") and certain shareholders of RCI (each, a "Seller")
have entered into a Stock Purchase Agreement dated as of May 8, 2000 (the "RCI
Stock Purchase Agreement"), providing for the purchase by the Company of all of
the outstanding shares of common stock of RCI. New World Broadcasters Corp.
("New World") and the Company have entered into an Asset Purchase Agreement
dated as of May 8, 2000 (the "Asset Purchase Agreement"), providing for the
purchase by the Company of Radio Station KTCY-FM (the "Station") and certain
other assets and liabilities related to the Station. The undersigned has or may
receive shares of Common Stock (as defined below) in connection with the RCI
Stock Purchase Agreement and/or the Asset Purchase Agreement.

               In consideration of the execution of the RCI Stock Purchase
Agreement and the Asset Purchase Agreement by the Company and for other good and
valuable consideration, the undersigned hereby irrevocably agrees that, without
the Company's prior written consent, the undersigned will not, directly or
indirectly, for the time periods set forth below, (1) offer for sale, sell,
pledge, or otherwise dispose of (or enter into any transaction or device that is
designed to, or could be expected to, result in the disposition by any person at
any time in the future of) any shares of the Company's Class A Common Stock, par
value $.0001 per share (the "Common Stock"), transferred or to be transferred,
directly or indirectly, to the undersigned, in connection with the RCI Stock
Purchase Agreement or the Asset Purchase Agreement, respectively; provided that
the undersigned may at any time distribute all or a portion of the shares of
Common Stock to an Affiliate (as defined in the RCI Stock Purchase Agreement and
the Asset Purchase Agreement) of the undersigned so long as such Affiliate
agrees to comply with the restrictions contained in this Lock-Up Letter
Agreement (this "Agreement") and the Company has given its prior approval
thereto or (2) enter into any swap or other derivatives transactions that
transfers to another, in whole or in part, any of the economic benefits or risks
of ownership of such shares of Common Stock, whether any such transaction
described in clause (1) or (2) above is to be settled by delivery of Common
Stock or other securities, in cash or otherwise, except in accordance with the
terms of this Agreement (clause (1) and (2) collectively, the "Prohibited
Transfers").

               The undersigned agrees that it may only effect a Prohibited
Transfer (i) with respect to 40% of the aggregate Common Stock held by the
undersigned, after the first anniversary of the Closing Date (as that term is
defined in the RCI Stock Purchase Agreement and the Asset Purchase Agreement)
has passed, and (ii) with respect to the remaining 60% of the

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aggregate Common Stock held by the undersigned, after the second anniversary of
the Closing Date has passed.

               In furtherance of the foregoing, you and your Transfer Agent are
hereby authorized to decline to make any transfer of securities if such transfer
would constitute a violation or breach of this Agreement.

               This Lock-Up Letter Agreement supersedes any and all prior
Lock-Up Letter Agreement(s) relating to the RCI Stock Purchase Agreement and the
Asset Purchase Agreement entered into by the undersigned.

               The undersigned hereby represents and warrants that the
undersigned has full power and authority to enter into this Agreement and that,
upon request, the undersigned will execute any additional documents necessary in
connection with the enforcement hereof. Any obligations of the undersigned shall
be binding upon the heirs, personal representative, successors and assigns of
the undersigned.

                                                   Very truly yours,

Date: March 13, 2001                               /s/ James A. Gammon
                                                   -------------------------
                                                       James A. Gammon

                                       2<PAGE>   1
                                                                     EXHIBIT 4.8

                                   LOCK-UP LETTER AGREEMENT

Spanish Broadcasting System, Inc.
3191 Coral Way
Suite 805
Miami, Florida 33145

Dear Sirs:

               Spanish Broadcasting System, Inc., or its successor or assign
(the "Company"), Rodriguez Communications, Inc. ("RCI"), Viva Broadcasting, LLC
("Viva"), Elias Liberman, Julio D. Liberman and Jason J. Liberman (Viva and the
Libermans, collectively the "Libermans") have entered into a Release and
Termination Agreement, dated as of May 6, 2000 (the "Release Agreement"). In
connection with the Release Agreement and as designees of the Libermans
thereunder, each of the undersigned shall receive shares of Common Stock (as
defined below) of the Company.

               In consideration of the execution of the Release Agreement by the
Company and for other good and valuable consideration, each of the undersigned
hereby irrevocably agrees that, without the Company's prior written consent,
each of the undersigned will not, directly or indirectly, for the time periods
set forth below, (1) publicly offer for sale, sell, pledge, or otherwise dispose
of (or enter into any transaction or device that is designed to, or could be
expected to, result in the disposition by any person at any time in the future
of) any shares of the Company's Class A Common Stock, par value $.0001 per share
(the "Common Stock") transferred or to be transferred, directly or indirectly,
to the undersigned as designees of the Libermans, in connection with the Release
Agreement or (2) enter into any swap or other derivatives transactions that
transfers to another, in whole or in part, any of the economic benefits or risks
of ownership of such shares of Common Stock, whether any such transaction
described in clause (1) or (2) above is to be settled by delivery of Common
Stock or other securities, in cash or otherwise, except in accordance with the
terms of this Lock-Up Letter Agreement (this "Agreement") (clause (1) and (2)
collectively, the "Prohibited Transfers"). Notwithstanding the foregoing
Prohibited Transfers, the undersigned may offer for sale, sell, pledge or
dispose of its and/or their shares of Common Stock in the Company at any time
after issuance of the Common Stock (as provided for in the Release Agreement),
in a private transaction on the condition that the recipient of the shares of
Common Stock agrees to be bound by the terms of the lock-up provisions outlined
in the following paragraph.

               Each of the undersigned agree that they shall not effect a
Prohibited Transfer (i) with respect to 6% of the aggregate Common Stock held by
any of the undersigned, until the Closing Date (as defined in the RCI Stock
Purchase Agreement) has passed, (ii) with respect to 14% of the aggregate Common
Stock held by any of the undersigned, until March 15, 2001 has passed, (iii)
with respect to 40% of the aggregate Common Stock held by any of the
undersigned, until the first anniversary of the Closing Date has passed, and
(iv) with respect to 40% of the

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aggregate Common Stock held by any of the undersigned, until the second
anniversary of the Closing Date has passed.

               In furtherance of the foregoing, you and your Transfer Agent are
hereby authorized to decline to make any transfer of securities if such transfer
would constitute a violation or breach of this Agreement.

               Each of the undersigned hereby represent and warrant that each of
the undersigned has full power and authority to enter into this Agreement and
that, upon request, each of the undersigned will execute any additional
documents necessary in connection with the enforcement hereof. Any obligations
of any of the undersigned shall be binding upon the heirs, personal
representatives, successors and assigns of any of the undersigned.

                                             Very truly yours,

                                             The Julio and Ida Liberman Trust
Date: November 10, 2000

                                             By:  /s/  Julio D. Liberman
                                                -------------------------
                                                Name:  Julio D. Liberman
                                                Title: Trustee

                                             The Elias and Miriam Liberman Trust

                                             By:  /s/  Elias Liberman
                                                -------------------------
                                                Name:  Elias Liberman
                                                Title: Trustee

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                                                                     EXHIBIT 4.9

                            LOCK-UP LETTER AGREEMENT

Spanish Broadcasting System, Inc.
3191 Coral Way
Suite 805
Miami, Florida 33145

Dear Sirs:

               Spanish Broadcasting System, Inc., or its successor or assign
(the "Company"), Rodriguez Communications, Inc. ("RCI"), Viva Broadcasting, LLC
("Viva"), Elias Liberman, Julio D. Liberman and Jason J. Liberman (Viva and the
Libermans, collectively the "Libermans") have entered into a Release and
Termination Agreement, dated as of May 6, 2000 (the "Release Agreement"). As a
transferee of the Libermans, the undersigned shall receive shares of Common
Stock (as defined below) of the Company.

               In consideration of the execution of the Release Agreement by the
Company and for other good and valuable consideration, the undersigned hereby
irrevocably agrees that, without the Company's prior written consent, the
undersigned will not, directly or indirectly, for the time periods set forth
below, (1) publicly offer for sale, sell, pledge, or otherwise dispose of (or
enter into any transaction or device that is designed to, or could be expected
to, result in the disposition by any person at any time in the future of) any
shares of the Company's Class A Common Stock, par value $.0001 per share (the
"Common Stock") transferred or to be transferred, directly or indirectly, to the
undersigned as a transferee of the Libermans, or (2) enter into any swap or
other derivatives transactions that transfers to another, in whole or in part,
any of the economic benefits or risks of ownership of such shares of Common
Stock, whether any such transaction described in clause (1) or (2) above is to
be settled by delivery of Common Stock or other securities, in cash or
otherwise, except in accordance with the terms of this Lock-Up Letter Agreement
(this "Agreement") (clause (1) and (2) collectively, the "Prohibited
Transfers"). Notwithstanding the foregoing Prohibited Transfers, the undersigned
may offer for sale, sell, pledge or dispose of its shares of Common Stock in the
Company at any time after issuance of the Common Stock (as provided for in the
Release Agreement), in a private transaction on the condition that the recipient
of the shares of Common Stock agrees to be bound by the terms of the lock-up
provisions outlined in the following paragraph.

               The undersigned agrees that it will not effect a Prohibited
Transfer (i) with respect to 6% of the aggregate Common Stock held by the
undersigned, until the Closing Date (as defined in the RCI Stock Purchase
Agreement) has passed, (ii) with respect to 14% of the aggregate Common Stock
held by the undersigned, until March 15, 2001 has passed, (iii) with respect to
40% of the aggregate Common Stock held by the undersigned, until the first
anniversary of the Closing Date has passed, and (iv) with respect to 40% of the
aggregate Common Stock held by the undersigned, until the second anniversary of
the Closing Date has passed.

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               In furtherance of the foregoing, you and your Transfer Agent are
hereby authorized to decline to make any transfer of securities if such transfer
would constitute a violation or breach of this Agreement.

               The undersigned hereby represents and warrants that the
undersigned has full power and authority to enter into this Agreement and that,
upon request, the undersigned will execute any additional documents necessary in
connection with the enforcement hereof. Any obligations of the undersigned shall
be binding upon the heirs, personal representatives, successors and assigns of
the undersigned.

                                                  Very truly yours,

                                                  The Liberman Irrevocable Trust
Date: February 26, 2001
                                                     By: /s/ Jason J. Liberman
                                                        -----------------------
                                                         Name: Jason J. Liberman
                                                         Title: Trustee

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