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                                                                   Exhibit 10.37

                          PLEDGE AND SECURITY AGREEMENT

        This Pledge and Security Agreement (the "Agreement") is made and entered
into effective as of April 2, 2001, by and between Michael L. Robertson
("Borrower"), on the one hand, and MP3.com, Inc., a Delaware corporation
("Lender" or the "Company"), on the other, pursuant to that certain Secured
Promissory Note of even date herewith executed by Borrower in favor of Lender
(the "Note"). This Agreement, the Note, the Escrow Agreement (as defined below)
and all other documents and instruments executed in connection herewith or
therewith, are collectively referred to as the "Loan Documents."

        IN CONSIDERATION of Lender's agreement to make the loan pursuant to the
Note, and other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, Borrower agrees as follows:

        1. Pledge of Stock and Creation of Security Interest. To secure the
timely payment and performance of the Secured Obligations (as defined below),
Borrower hereby collaterally assigns and pledges to Lender, and grants to Lender
a security interest in, all the right, title and interest of Borrower, now owned
or hereafter acquired, in, to and under the collateral described in Section 2
herein below, and the proceeds thereof (the "Collateral"). The Collateral shall
be held in escrow pursuant to the terms of an Escrow Agreement between Borrower,
Lender and the Escrow Agent named therein (the "Escrow Agent") of even date
herewith (the "Escrow Agreement") until such time as all amounts due under the
Loan Documents have been paid in full.

        2. Collateral. The Collateral shall consist of all unencumbered shares
of Common Stock of the Company held by Borrower, which amount shall be no fewer
than 19.7 million shares of Common Stock of the Company. If, following the date
hereof, there occurs any stock dividend, stock split, recapitalization or other
change affecting the Common Stock of the Company as a class effected without
receipt of consideration, any new, substituted or additional securities or other
property that is by reason of such transaction distributed with respect to
Common Stock of the Company that comprises the Collateral shall be immediately
delivered by Borrower to Lender to be held as Collateral. If, following the date
hereof, there occurs any dividend, distribution, merger, consolidation, share
exchange or reorganization affecting the Common Stock of the Company, then any
new, substituted or additional securities or other property (including money
paid as a regular cash dividend) that is by reason of such transaction
distributed with respect to the Collateral shall be immediately delivered by
Borrower to Lender to be held as Collateral. In the event any cash is deposited
as part of the Collateral pursuant hereto, the parties will make appropriate
amendments to this Agreement to include investment provisions and controls for
such cash.

        Notwithstanding the foregoing, and notwithstanding any partial payments
of principal or interest by Borrower, at no time prior to the repayment in full
of all amounts due under the Loan Documents shall any Collateral, or any part
thereof, be released or returned to Borrower.

        The Borrower shall deliver the Collateral to Lender by delivering the
Collateral, together with stock powers executed in blank, to the Escrow Agent at
MP3.com, Inc. 4790 Eastgate Mall, San Diego, CA 92121-1970 Attn. Secretary, or
to such other person or address as shall be designated by the Chief Financial
Officer of the Company in writing.
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        3. Secured Obligations of Borrower. The Collateral secures and shall
hereafter secure (i) the payment by Borrower to Lender of all indebtedness now
or hereafter owed pursuant to the Loan Documents to Lender by Borrower,
including, without limitation, the loan made to Borrower pursuant to the Note,
together with any interest thereon and extensions, modifications and renewals
thereof, (ii) the payment by Borrower, or reimbursement to Lender, of all fees,
costs or expenses to be paid, incurred or borne by Borrower pursuant to any of
the Loan Documents, and (iii) the performance by Borrower of all other
obligations and the discharge of all other liabilities to Lender of every kind
and character, direct or indirect, absolute or contingent, due or to become due,
now existing or hereafter arising under this Agreement or any of the other Loan
Documents (the foregoing are collectively referred to as the "Secured
Obligations"). All payments and performance shall be in accordance with the
terms of the Loan Documents. Borrower shall reimburse Lender on demand for any
and all amounts expended by Lender in accordance with, or in the enforcement
(judicially or otherwise) or exercise of its rights under, the terms of this
Agreement, including attorneys' fees, which amounts are included in the Secured
Obligations secured hereunder.

        4. Borrower's Representations and Warranties. Borrower represents and
warrants that:

            (a) Borrower is (or to the extent that this Agreement states that
the Collateral is to be acquired after the date hereof, will be) the sole owner
of the Collateral; upon delivery of the Collateral to Lender the security
interest hereunder in the Collateral will be a first, prior and perfected
security interest; there are no security interests, liens or encumbrances, or
adverse claims of title to, community property interests in, or any other
interest whatsoever in, the Collateral or any portion thereof except that
created by this Agreement; and no financing statement, mortgage or deed of trust
covering the Collateral or any portion thereof exists or is on file in any
public office; and

            (b) Borrower has the full power and authority to pledge, transfer
and assign the Collateral to Lender, and such pledge, transfer and assignment to
Lender will not violate any federal or state law, rule or regulation, including
without limitation federal or state securities laws; and

            (c) No part of the Collateral is subject to a risk of forfeiture or
vesting provisions applicable to Borrower pursuant to the terms of the
instrument pursuant to which Borrower acquired the Collateral; and

            (d) Neither the execution and delivery of this Agreement by Borrower
nor the consummation of the transactions herein contemplated nor the fulfillment
of the terms hereof will result in a breach of any of the terms or provisions
of, or constitute a default under, or constitute an event which with notice or
lapse of time or both will result in a breach of or constitute a default under,
any material agreement, indenture, mortgage, deed of trust, equipment lease or
other instrument to which Borrower is a party, or conflict with any law, order,
rule or regulation applicable to Borrower of any court or any federal or state
government, regulatory body or administrative agency, or any other governmental
body having jurisdiction over Borrower or Borrower's properties.

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        5. Covenants of Borrower. Borrower covenants that:

            (a) Borrower will defend the Collateral against all claims and
demands of all third parties at any time claiming the same or any interest
therein;

            (b) Borrower will, promptly upon request by Lender, procure or
execute and deliver any document, give any notices, execute and file any
financing statements, mortgages or other documents, all in form and substance
satisfactory to Lender, mark any chattel paper, deliver any chattel paper or
instruments to Lender and take any other actions which are necessary or, in the
judgment of Lender, desirable to perfect or continue the perfection and first
priority of Lender's security interest in the Collateral, to protect the
Collateral against the rights, claims, or interests of third persons or to
effect the purposes of this Agreement, and will pay all costs incurred in
connection therewith;

            (c) Borrower will not, without the prior written consent of Lender,
in any way hypothecate or create or permit to exist any lien, security interest
or encumbrance on or other interest in the Collateral except that created by
this Agreement, nor will Borrower sell, transfer, assign, exchange or otherwise
dispose of the Collateral or any option with respect thereto. If the Collateral,
or any part thereof, is sold, transferred, assigned, exchanged, or otherwise
disposed of in violation of these provisions, the security interest of Lender
shall continue in such Collateral or part thereof notwithstanding such sale,
transfer, assignment, exchange or other disposition, and Borrower will hold the
proceeds thereof in a separate account for Lender's benefit. Borrower will, at
Lender's request, transfer such proceeds to Lender in kind;

            (d) Borrower will pay and discharge all taxes, assessments and
governmental charges or levies against the Collateral prior to delinquency
thereof and will keep the Collateral free of all unpaid charges whatsoever; and

            (e) Lender shall have the right to make any payments and do any
other acts Lender may deem necessary to protect its security interest in the
Collateral, including, without limitation, the rights to pay, purchase, contest
or compromise any encumbrance, charge or lien which in the judgment of Lender
appears to be prior to or superior to the security interest granted hereunder,
and appear in and defend any action or proceeding purporting to affect its
security interest in and/or the value of the Collateral, and in exercising any
such powers or authority, the right to pay all expenses incurred in connection
therewith, including attorneys' fees. Borrower hereby agrees to reimburse Lender
for all payments made and expenses incurred, which amounts shall be secured
under this Agreement, and agrees it shall be bound by any payment made or act
taken by Lender hereunder. Lender shall have no obligation to make any of the
foregoing payments or perform any of the foregoing acts.

        6. Defaults and Remedies. Upon the occurrence and during the
continuation of an Event of Default (as described and defined in the Note),
Lender may, at its option, without notice to or demand upon Borrower, do any one
or more of the following:

               (a) Declare all advances made by Lender to Borrower under the
        Note and all other Secured Obligations to be immediately due and
        payable, whereupon all unpaid principal and interest on all advances and
        other Secured Obligations shall become and be immediately due and
        payable;

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               (b) Exercise any or all of the rights and remedies provided for
        by the applicable Uniform Commercial Code, specifically including,
        without limitation, the right to recover the attorneys' fees and other
        expenses incurred by Lender in the enforcement of this Agreement or in
        connection with Borrower's redemption of the Collateral;

               (c) Sell all or any portion of the Collateral in any commercially
        reasonable manner in any one or more public or private sales, at the
        sole discretion of Lender, or proceed by an action or actions at law or
        in equity to recover the Secured Obligations. Borrower agrees that any
        sale of all or any portion of the Collateral in the public market, in
        compliance with applicable federal and state securities laws and
        regulations, shall be conclusively presumed to be commercially
        reasonable. Lender shall also have the right and option to purchase all
        or any portion of the Collateral from Borrower at a price equal to the
        "Fair Market Value" of such Collateral. The "Fair Market Value" per
        share of Common Stock of the Company shall be equal to the average of
        the closing price per share of Common Stock of the Company as reported
        by The Nasdaq Stock Market's National Market System or such other
        securities exchange, market or quotation system on which Common Stock of
        the Company is then listed for trading or quoted on each of the ten (10)
        trading days prior to the date of purchase. Any consideration owed to
        Borrower for any such purchase shall be first offset against the Secured
        Obligations, with any excess consideration to be paid in cash to
        Borrower; and

               (d) Enforce one or more remedies hereunder, successively or
        concurrently, and such action shall not operate to estop or prevent
        Lender from pursuing any other or further remedy which it may have, and
        any repossession or retaking or sale of the Collateral pursuant to the
        terms hereof shall not operate to release Borrower until full and final
        payment of any deficiency has been made in cash. Borrower shall
        reimburse Lender upon demand for, or Lender may apply any proceeds of
        Collateral to, the costs and expenses (including attorneys' fees,
        transfer taxes and any other charges) incurred by Lender in connection
        with any sale, disposition or retention of any Collateral hereunder.

        7. Miscellaneous Provisions.

            (a) Notices. Any and all notices required by this Agreement shall be
delivered or sent in the manner and to the addresses set forth in the Note.

            (b) Headings. The various headings in this Agreement are inserted
for convenience only and shall not affect the meaning or interpretation of this
Agreement or any provision hereof.

            (c) Governing Law. This Agreement shall be construed in accordance
with and all disputes hereunder shall be governed by the internal laws of the
State of California without regard to principles of conflicts of laws.

            (d) No Waiver; Amendments. No delay in enforcing or failure to
enforce any right under this Agreement by Lender shall constitute a waiver by
Lender of such right. No waiver by Lender of any default hereunder shall be
effective unless in writing, nor shall any waiver operate as a waiver of any
other default or of the same default on a future occasion. This

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Agreement or any provision hereof may be changed, waived or terminated only by a
statement in writing signed by the party against which such change, waiver or
termination is sought to be enforced.

            (e) Time of the Essence. Time is of the essence of each provision of
this Agreement of which time is an element.

            (f) Binding Agreement. All rights of Lender hereunder shall inure to
the benefit of its successors and assigns. Borrower shall not assign any of its
interest under this Agreement without the prior written consent of Lender. Any
purported assignment inconsistent with this provision shall, at the option of
Lender, be null and void.

            (g) Entire Agreement. This Agreement, together with the Note and any
other agreement executed in connection herewith, is intended by the parties as a
final expression of their agreement and is intended as a complete and exclusive
statement of the terms and conditions thereof.

            (h) Attorneys' Fees. In any action or proceeding brought to enforce
any provision of this Agreement, or to seek damages for a breach of any
provision hereof, the successful party shall be entitled to recover reasonable
attorneys' fees in addition to any other available remedy.

            (i) Severability. If any provision of this Agreement should be found
to be invalid or unenforceable, all of the other provisions shall nonetheless
remain in full force and effect to the maximum extent permitted by law.

            (j) Survival of Provisions. All representations, warranties and
covenants of Borrower contained herein shall survive the execution and delivery
of this Agreement, and shall terminate only upon the full and final payment and
performance by Borrower of the Secured Obligations.

            (k) Setoff. Lender shall have the right, at any time, to set off any
indebtedness or obligation of Borrower under the Loan Documents against any
indebtedness or obligation of Lender, without notice to or demand upon Borrower
and whether or not any such indebtedness or obligations are liquidated or mature
at the time of such offset. Lender's right of offset hereunder shall be in
addition to and not in limitation of any other rights or remedies which may
exist in favor of Lender.

            (l) Power of Attorney. Borrower hereby appoints and constitutes
Lender as Borrower's attorney-in-fact, effective upon the occurrence of and
during the continuation of an Event of Default (as defined in the Note), for
purposes of (i) collecting accounts or proceeds of any Collateral, (ii)
conveying any item of Collateral to any purchaser thereof, and (iii) making any
payments or taking any acts under Section 5(e) hereof. Lender's authority
hereunder shall include, without limitation, the authority to endorse and
negotiate, for Lender's own account, any checks or instruments in the name of
Borrower, to execute any receipt for any certificate of ownership or any
document, to transfer title to any item of Collateral, and to take any other
actions necessary or incident to the powers granted to Lender in this Agreement.
This power of attorney is coupled with an interest and is irrevocable by
Borrower until full and final payment of all of the Secured Obligations.

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            (m) Authority of Lender. Lender shall have and be entitled to
exercise all powers hereunder which are specifically delegated to Lender by the
terms hereof, together with such powers as are reasonably incident thereto.
Lender may perform any of its duties hereunder or in connection with the
Collateral by or through agents or employees and shall be entitled to retain
counsel and to act in reliance upon the advice of counsel concerning all such
matters. Neither Lender nor any director, officer, employee, attorney or agent
of Lender shall be liable to Borrower for any action taken or omitted to be
taken by it or them hereunder, except for its or their own willful misconduct;
nor shall Lender be responsible for the validity, effectiveness or sufficiency
hereof or of any document or security furnished pursuant hereto. Lender and they
shall be entitled to rely on any communication, instrument or document believed
by it or them to be genuine and correct and to have been signed or sent by the
proper person or persons. Borrower agrees to indemnify and hold harmless Lender
and/or any such other person from and against any and all costs, expenses
(including attorneys' fees), claims or liability incurred by Lender or such
person hereunder, unless such claim or liability shall be due to willful
misconduct on the part of Lender or such person.

            (n) Statute of Limitations. Borrower hereby waives the right to
plead any statute of limitations as a defense to any obligation hereunder or any
of the Secured Obligations to the full extent permitted by law.

            (o) Counterparts. This Agreement may be executed in one or more
counterparts, each of which shall be deemed an original but all of which shall
together constitute one and the same agreement.

            (p) Termination of the Agreement. This Agreement shall terminate
upon full and final payment and performance of all of the Secured Obligations.
At such time, Lender shall reassign and redeliver to Borrower all of the
Collateral hereunder which has not been sold, disposed of, retained or applied
by Lender in accordance with the terms hereof. Such reassignment and redelivery
shall be without warranty by or recourse to Lender (provided that such
Collateral shall not be transferred or encumbered by Lender except as permitted
under the Loan Documents) and shall be at the sole expense of Borrower.



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        IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
duly executed and delivered as of the date first written above.


                                            "Borrower"

                                            Michael L. Robertson


                                               /s/ Michael L. Robertson
                                            ------------------------------------


                                            "Lender"

                                            MP3.com, Inc.

                                            By:    /s/ Paul L. H. Ouyang
                                                --------------------------------
                                            Name:  Paul L. H. Ouyang
                                                   -----------------------------
                                            Title: EVP, CFO
                                                   -----------------------------



















                 Signature Page to Pledge and Security Agreement
                               dated April 2, 2001



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