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                                                                  EXHIBIT 10.13



                           NETSHOW LICENSE AGREEMENT

This NetShow License Agreement (the "Agreement") is entered into and effective
as of August 5, 1997 (the "Effective Date") by and between MICROSOFT
CORPORATION, a Washington corporation located at One Microsoft Way, Redmond, WA
98052 ("Microsoft") and AUDIONET, INC., a Delaware corporation located at 2914
Taylor Street, Dallas, TX 75226 ("AudioNet").

                                    RECITALS

Microsoft is the owner and/or authorized licensor of a line of Internet
streaming audio and video client and server technology known as NetShow.

Under this Agreement, Microsoft wishes to grant, and AudioNet wishes to
receive, a license [*] 

The parties hereby agree as follows:

                                   AGREEMENT

1.       DEFINITIONS

1.1      "AudioNet Services Support" means [*]

1.2      "AudioNet Services" means [*]

1.3      "Beta Quality" means software which passes system testing, contains
         substantially all of the intended core features, is ready for
         production testing and contains a limited number of significant
         errors.

1.4      "Confidential Information" means: (i) any source code of Microsoft
         Software; and (ii) the terms and conditions of this Agreement.
         "Confidential Information" shall not include information that: (a) is
         or becomes generally known or available by publication, commercial use
         or otherwise through no fault of the receiving party; (b) is known and
         has been reduced to tangible form by the receiving party at the time
         of disclosure and is not subject to restriction; (c) is independently
         developed or learned by the receiving party; (d) is lawfully obtained
         from a third party that has, to the knowledge of the receiving party,
         the right to make such disclosure; or (e) is made generally available
         by the disclosing party without restriction on disclosure.

1.5      "Microsoft Software" means NetShow, [*]

1.6      "NetShow" means [*]

1.7      [*]


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1.8      "Production Quality" means software which has either no significant
         errors or only significant errors which are documented and mutually
         agreed to be rare or remote in likelihood of occurrence, and which has
         passed mutual, reasonable acceptance criteria during beta testing in a
         production environment.

1.9      "Term" [*]

1.10     "Third Party Contractor" means a third party company or other entity
         under written agreement with AudioNet to perform AudioNet Services
         Support, where such written agreement is consistent with the terms and
         conditions of this Agreement including, but not limited to, Sections 3
         and 6.

1.11     "Updates" means, as to any Microsoft Software, all subsequent public
         releases (including maintenance releases) thereof by Microsoft during
         the Term, including public releases of error corrections, upgrades,
         enhancements, additions, improvements, extensions, modifications and
         successor versions, for which Microsoft has the right to license to
         AudioNet.

1.12     [*]

2.       DELIVERY

2.1      NetShow. Microsoft shall deliver to AudioNet, on such media as AudioNet
         reasonably requests, a copy of [*] within five (5) days after the
         Effective Date. Updates of NetShow which are separate release versions
         shall be delivered to AudioNet as follows:


         BETA QUALITY                [*]
         ---------------------------------------------------------------
         PRODUCTION QUALITY          [*]

2.2      [*]

2.3      [*]

3.       OBJECT CODE LICENSE GRANTS

3.1      License Grant - NetShow [*]. Microsoft hereby grants to
         AudioNet a [*]
         license to use [*]


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         [*]

3.2      License Grant - [*]. Microsoft hereby grants to AudioNet a
         [*]

3.3      Ownership. Except as expressly licensed to AudioNet in Sections 3.1
         and 3.2, Microsoft retains all right, title and interest in and to the
         Microsoft Software.

3.4      No Distribution/Other Rights. AudioNet agrees that this Agreement does
         not grant to it any distribution or resale rights to the Microsoft
         Software, in any form (except solely with respect to the rent and/or
         reuse of connections or streams or the sublicense rights to Third
         Party Contractors, as provided in Sections 3.1 and 3.2, respectively).
         Except as expressly granted in this Agreement, AudioNet shall have no
         other rights in the Microsoft Software. Under no circumstances will
         the license grant set forth in Sections 3.1 and 3.2 be construed as
         granting, by implication, estoppel or otherwise, a license to any
         Microsoft technology other than the Microsoft Software.

4.       NONEXCLUSIVE

Nothing in this Agreement will be construed as restricting Microsoft's ability
to license, develop, sublicense, manufacture, deploy or distribute Microsoft
Software or any other technology, for itself or for or to any third party.

5.       CONSIDERATION

As partial consideration for the licenses under this Agreement, AudioNet shall,
[*], pay Microsoft the license fee set forth in Exhibit B.

6.       CONFIDENTIALITY

6.1      The confidentiality provisions of this Agreement shall only apply to
         disclosures regarding the terms, conditions and existence of this
         Agreement. All other disclosures of Confidential Information shall be
         pursuant a separate, confidentiality agreement between the parties
         executed as of the Effective Date. Each party shall protect the
         other's Confidential Information from unauthorized dissemination and
         use with the same degree of care that such party uses to protect its
         own like information. Neither party will use the other's Confidential
         Information for purposes other than those necessary to directly
         further the purposes of this Agreement. Each party will use its best
         efforts not to disclose to third parties the other's Confidential
         Information without the prior written consent of the other party.
         Except as expressly provided in this Agreement, no ownership or
         license rights is granted in any Confidential Information.

6.2      The parties' obligations of confidentiality under this Agreement shall
         not be construed to limit either party's right to independently
         develop or acquire products without use of the other party's


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         Confidential Information. Further, either party shall be free to use
         for any purpose the residuals resulting from access to or work with
         such Confidential Information, provided that such party shall maintain
         the confidentiality of the Confidential Information as provided
         herein. The term "residuals" means information in non-tangible form,
         which may be retained by persons who have had rightful and good faith
         access to the Confidential Information, including ideas, concepts,
         know-how or techniques contained therein. Neither party shall have any
         obligation to limit or restrict the assignment of such persons or to
         pay royalties for any work resulting from the use of residuals.
         However, the foregoing shall not be deemed to grant to either party a
         license under the other party's copyrights or patents.

6.3      Microsoft hereby consents to the following limited disclosures of
         Microsoft Confidential Information: (i) AudioNet may disclose the
         existence of this Agreement; (ii) AudioNet may disclose the terms of
         this Agreement to third party customers, suppliers and current and
         prospective investors solely as provided in Exhibit C; and (iii)
         AudioNet may disclose this Agreement as required by applicable law,
         rule or regulation, including without limitation the Securities Act of
         1933, as amended, the Securities Exchange Act of 1934, as amended
         (the "Exchange Act"), and the rules and regulations promulgated by the
         Securities and Exchange Commission (the "SEC") thereunder; provided
         that, AudioNet shall (a) give written notice to Microsoft prior to
         such disclosure and shall comply with any protective order or
         equivalent that Microsoft obtains and (b) cooperate with Microsoft in
         structuring a SEC Rule 406 request for confidential treatment with
         respect to as many of the terms of this Agreement as may reasonably be
         achieved.

7.       WARRANTIES

7.1      Microsoft warrants and represents that the Microsoft Software, to the
         best of its knowledge, does not infringe any third party copyright,
         patent or trade secret.

7.2      AudioNet warrants and represents that the AudioNet Services, to the
         best of its knowledge, shall not infringe any third party copyright,
         patent or trade secret.

8.       DISCLAIMER OF FURTHER WARRANTIES

EXCEPT AS EXPRESSLY WARRANTED IN SECTION 7.1, THE MICROSOFT SOFTWARE IS
PROVIDED TO AUDIONET "AS IS" WITHOUT FURTHER WARRANTY OF ANY KIND. MICROSOFT
DISCLAIMS ALL FURTHER WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
PURPOSE, TITLE AND NONINFRINGEMENT.

EXCEPT AS EXPRESSLY WARRANTED IN SECTION 7.2, THE AUDIONET SERVICES ARE
PROVIDED "AS IS" WITHOUT FURTHER WARRANTY OF ANY KIND. AUDIONET DISCLAIMS ALL
FURTHER WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO,
THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE,
TITLE AND NONINFRINGEMENT.

9.       INDEMNITY

9.1      By Microsoft.

         (a)     Microsoft shall, at its expense and AudioNet's request, defend
                 any claim or action brought against AudioNet, or any of
                 AudioNet's subsidiaries, affiliates, directors, officers,
                 employees,



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                 agents and independent contractors, to the extent such claim
                 or action is based upon a claim (i) that the Microsoft
                 Software infringes or violates any patent, copyright,
                 trademark, trade secret or other proprietary right of a third
                 party or (ii) that Microsoft does not have the rights to grant
                 AudioNet the rights granted in Section 3 ("Microsoft Claims"),
                 and Microsoft will indemnify and hold AudioNet harmless from
                 and against any costs, damages and fees reasonably incurred by
                 AudioNet, including but not limited to fees of attorneys and
                 other professionals, as a result of such Microsoft Claims.
                 AudioNet shall: (i) provide Microsoft reasonably prompt notice
                 in writing of any such Microsoft Claims and permit Microsoft,
                 through counsel mutually acceptable to AudioNet and Microsoft,
                 to answer and defend such Microsoft Claims; and (ii) provide
                 Microsoft information, assistance and authority, at
                 Microsoft's expense, to help Microsoft to defend such
                 Microsoft Claims. Microsoft will be responsible for any
                 settlement made by AudioNet only if Microsoft's written
                 permission has been obtained, which permission will not be
                 unreasonably withheld.

         (b)     Microsoft may not settle any Microsoft Claim under this
                 Section 9.1 on AudioNet's behalf without first obtaining
                 AudioNet's written permission, which permission will not be
                 unreasonably withheld. In the event AudioNet and Microsoft
                 agree to settle a Microsoft Claim, Microsoft agrees not to
                 publicize the settlement without first obtaining AudioNet's
                 written permission, which permission will not be unreasonably
                 withheld.

         (c)     The obligations of this Section 9.1 shall be AudioNet's
                 exclusive remedy for any breach of Microsoft's warranties
                 under Section 7.

         (d)     Notwithstanding anything to the contrary in this Section 9.1,
                 Microsoft shall have no obligation to indemnify and hold
                 AudioNet harmless with respect to any breach of contract claim
                 made against AudioNet under a contract between AudioNet and
                 any third party.

9.2      By AudioNet.

         (a)     [*]

         (b)     AudioNet may not settle any AudioNet Claim under this Section
                 9.2 on Microsoft's behalf without first obtaining Microsoft's
                 written permission, which permission will not be unreasonably
                 withheld. In the event Microsoft and AudioNet agree to settle
                 an AudioNet Claim, AudioNet agrees not to publicize the
                 settlement without first obtaining Microsoft's written
                 permission, which permission will not be unreasonably
                 withheld.

         (c)     The obligations of this Section 9.2 shall be Microsoft's
                 exclusive remedy for any breach of AudioNet's warranties under
                 Section 7.2.



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10.      TERMINATION

10.1     Term. Unless earlier terminated in accordance with Section 10.2, this
         Agreement shall commence upon the Effective Date and continue in full
         force and effect through the Term.

10.2     Termination By Either Party For Cause. Either party may suspend
         performance and/or terminate this Agreement immediately upon written
         notice at any time if:

         (a)     The other party is in material breach of any material
                 warranty, term, condition or covenant of this Agreement, other
                 than those contained in Section 6, and fails to cure that
                 breach within sixty (60) days after written notice thereof; or

         (b)     The other party is in material breach of Section 6 and fails
                 to cure that breach within five (5) business days after
                 written notice thereof.

10.3     Effect of Termination.

         (a)     Neither party shall be liable to the other for damages of any
                 sort resulting solely from terminating this Agreement in
                 accordance with its terms.

         (b)     Should the Term of this Agreement expire or should this
                 Agreement be terminated by AudioNet for Microsoft's material
                 breach AudioNet's license grant under Section 3 shall survive
                 in perpetuity but only with respect to the then current
                 version of Microsoft Software in AudioNet's possession as of
                 the effective date of termination.

         (c)     Should this Agreement be terminated due to AudioNet's material
                 breach (other than a material breach of Sections 3 and 6),
                 AudioNet's license grants under Section 3 shall survive in
                 perpetuity, but only with respect to the versions of the
                 Microsoft Software in AudioNet's possession as of the
                 effective date of termination.

         (d)     Should this Agreement be terminated due to AudioNet's material
                 breach of Sections 3 or 6), AudioNet's license grants under
                 Section 3 shall not survive termination. Nothing in this
                 Section 11.3 shall limit Microsoft's ability to enforce its
                 rights and AudioNet's obligations under Sections 3 or 6 by
                 equitable relief such as injunction or specific performance.

10.4     Survival. In the event of termination or expiration of this Agreement
         for any reason, Sections 4, 6, 8, 9, 11 and 12 shall survive
         termination.

11.      LIMITATION OF LIABILITIES

IN NO EVENT SHALL EITHER PARTY BE LIABLE FOR ANY CONSEQUENTIAL, INDIRECT,
INCIDENTAL, PUNITIVE OR SPECIAL DAMAGES WHATSOEVER, INCLUDING WITHOUT
LIMITATION, DAMAGES FOR LOSS OF BUSINESS PROFITS, BUSINESS INTERRUPTION, LOSS
OF BUSINESS INFORMATION, AND THE LIKE, ARISING OUT OF THIS AGREEMENT OR THE USE
OF OR INABILITY TO USE THE MICROSOFT SOFTWARE OR EITHER PARTY'S CONFIDENTIAL
INFORMATION, EVEN IF A PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
DAMAGES.

THIS SECTION SHALL NOT APPLY TO SECTIONS 6 AND 9.



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12.      GENERAL PROVISIONS

12.1     Notices. All notices and requests in connection with this Agreement
         shall be deemed given as of the day they are received either by
         messenger, delivery service, or in the United States of America mails,
         postage prepaid, certified or registered, return receipt requested,
         and addressed as follows:

         TO AUDIONET:                         TO MICROSOFT:

         AudioNet, Inc.                       Microsoft Corporation
         2914 Taylor Street                   One Microsoft Way
         Dallas, TX 75226                     Redmond, WA 98052-6399
         Attention: Todd R. Wagner, CEO       Attention:
         Twagner@audionet.com
         Phone:  (214) 748-6656               Phone:   (425) 882-8080
         Fax:    (214) 748-6657               Fax:     (425) 936-7329
         Copy to:                             Copy to:
         Sean P. Griffiths                    Microsoft Corporation
         Gibson Dunn & Crutcher               One Microsoft Way
         200 Park Avenue                      Redmond, WA 98052-6399
         New York, NY 10012                   Attention: Law & Corporate Affairs
         sgriffiths@gdclaw.com
         Phone:  (212) 351-3872               Phone:   (425) 882-8080
         Fax:    (212) 351-4035               Fax:     (425) 936-7409

         or to such other address as a party may designate pursuant to this
         notice provision.

12.2     Independent Parties. Nothing in this Agreement shall be construed as
         creating an employer-employee relationship, a partnership, or a joint
         venture between the parties.

12.3     Governing Law. This Agreement shall be governed by the laws of the
         State of Washington.

12.4     Attorneys' Fees. In any action or suit to enforce any right or remedy
         under this Agreement or to interpret any provision of this Agreement,
         the prevailing party shall be entitled to recover its costs, including
         reasonable attorneys' fees.

12.5     Assignment. This Agreement shall be binding upon and inure to the
         benefit of each party's respective successors and lawful assigns;
         provided, however, that AudioNet may not assign its rights under this
         Agreement, in whole or in part, to any third party without the prior
         written approval of Microsoft. For purposes of this Agreement, a
         merger, consolidation, or other corporate reorganization in which
         AudioNet is not the surviving entity, the sale of all or substantially
         all of AudioNet's assets or the sale in a single transaction or a
         series of related transactions of more than 50% of the securities of
         AudioNet entitled to vote in the election of directors to a person or
         "group" (as such term is defined in the Exchange Act) other than any
         such group that may exist or be deemed to exist as of the date hereof,
         shall be deemed to be an assignment of this Agreement.

12.6     Construction. If for any reason a court of competent jurisdiction
         finds any provision of this Agreement, or portion thereof, to be
         unenforceable, that provision of the Agreement will be enforced to the
         maximum extent permissible so as to effect the intent of the parties,
         and the remainder of this Agreement will continue in full force and
         effect. Failure by either party to enforce any provision of this
         Agreement will not be deemed a waiver of future enforcement of that or
         any other provision. This Agreement has been negotiated by the parties
         and their respective counsel and will be interpreted fairly in
         accordance with its terms and without any strict construction in favor
         of or against either party.



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12.7     Entire Agreement. This Agreement does not constitute an offer by
         Microsoft and it shall not be effective until signed by both parties.
         This Agreement constitutes the entire agreement between the parties
         with respect, to the subject matter hereof and merges all prior and
         contemporaneous communications. It shall not be modified except by a
         written agreement dated subsequent to the date of this Agreement and
         signed on behalf of AudioNet and Microsoft by their respective duly
         authorized representatives.

IN WITNESS WHEREOF, the parties have entered into this Agreement as of the
Effective Date written above.

MICROSOFT CORPORATION                           AUDIONET, INC.

/s/ JIM DURKIN                                  /s/ MARK CUBAN
-----------------------------                   -----------------------------  
By (Sign)                                       By (Sign)                      
                                                                               
Jim Durkin                                      Mark Cuban
-----------------------------                   -----------------------------  
Name (Print)                                    Name (Print)                   
                                                                               
Product Unit Manager                            President
-----------------------------                   -----------------------------  
Title                                           Title                          
                                                                               
8/5/97                                          August 5, 1997
-----------------------------                   -----------------------------  
Date                                            Date                           



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                                   EXHIBIT A

                       DESCRIPTION OF MICROSOFT SOFTWARE

[*]


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                                   EXHIBIT B

                                 CONSIDERATION

[*]





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                                   EXHIBIT C

                         LIMITED THIRD PARTY DISCLOSURE

AudioNet may disclose the following in communications to its third party
customers, suppliers and current and prospective investors:

To be mutually agreed upon by the parties within five (5) days of the Effective
Date.




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