EXHIBIT 2.4
                                                                  
                                                                  EXECUTION COPY


                 FIRST AMENDMENT TO THE CONTRIBUTION AGREEMENT


          This First Amendment (this "Amendment"), dated as of March 18, 1999 to
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the certain Contribution Agreement (the "Contribution Agreement") dated as of
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February 19, 1999 between Capstar Broadcasting Corporation ("Capstar") and Muzak
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Holdings LLC (f/k/a ACN Holdings, LLC) ("ACN Holdings").
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     WHEREAS, Capstar and ACN Holdings (collectively, the "Parties") desire to
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amend the Contribution Agreement on the terms and conditions set forth herein.

     NOW THEREFORE, in consideration of the mutual agreements set forth herein,
the Parties agree as follows:

     1.   Capitalized Terms.  Capitalized terms used herein without definition
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shall have the meanings ascribed to such terms in the Contribution Agreement.

     2.   Working Capital Adjustment.  A new Section 2.4(m) is added to the
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Contribution Agreement to read in its entirety as follows:

          "(m)  Notwithstanding anything contained herein to the contrary, the
     parties hereto agree that for purposes of the First Closing, the "Estimated
     ACN Working Capital" shall be deemed to be a negative $17,880,870 (which
     amount represents solely the "Bridge Loan Payment") and the "Estimated
     First Closing Capstar Working Capital" shall be deemed to be zero.  As a
     result, the "Capstar Estimated First Closing WC Target" equals negative
     $4,605,718 and, as required by Section 2.4(d) hereof, at the First Closing,
     ACN Holdings shall pay to Capstar $4,605,718.

     3.   SCA Lease Agreement.  Section 4.16(a) of the Contribution Agreement is
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hereby amended in its entirety to read as follows:

          "4.16  SCA Lease Agreement.  Prior to the Second Closing, Capstar and
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     ACN Holdings shall negotiate in good faith the terms of Exhibits A and B to
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     the SCA Lease Agreement and such other modifications to the form of the SCA
     Lease Agreement attached as Exhibit D hereto as Capstar and ACN Holdings
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     may mutually agree."

     4.   Waivers.
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          (a) Each party hereto hereby waives the obligations pursuant to
     Sections 2.4(a) and 2.4(c) of the Contribution Agreement of the other party
     hereto and the failure to perform 

 
     or otherwise satisfy such obligations shall not constitute a breach of any
     covenant, agreement or condition of the Contribution Agreement.

          (b) ACN Holdings hereby waives the obligations of Capstar pursuant to
     Sections 5.3(c) and 6.2(a)(viii) to deliver the Consent of Muzak Limited
     Partnership and the failure to perform or otherwise satisfy such
     obligations shall not constitute a breach of any covenant, agreement or
     condition of the Contribution Agreement.

     5.   Consent.  Capstar hereby consents to ACN Holdings' and ACN's execution
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and delivery of (i) the Contribution Agreement, dated as of the date hereof (the
"Boyd Contribution Agreement"), among ACN Holdings, ACN and William Boyd and
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(ii) the First Amendment to the Agreement and Plan of Merger, dated as of the
date hereof (the "Amendment to the MLP Merger Agreement") among the parties to
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the MLP Merger Agreement.  ACN Holdings has delivered to Capstar complete copies
of the Boyd Contribution Agreement and the Amendment to the MLP Merger
Agreement.

     6.   Governing Law.  This Amendment shall be governed by and construed in
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accordance with the laws of the State of Delaware (without reference to its
rules as to conflicts of law).

     7.   Counterparts.  This Amendment may be executed in any number of
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counterparts, each of which shall be deemed an original, but all of which
together shall constitute a single instrument.

     8.   Agreement.  In all other respects the Contribution Agreement is
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ratified and shall, as so changed by these amendments, continue in full force
and effect.

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     IN WITNESS WHEREOF, the parties hereto have executed this Amendment as of
the date first set forth above.


                                        MUZAK HOLDINGS LLC


                                        By: /s/ Royce Yudkoff
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                                           Name:  Royce Yudkoff
                                           Title: Executive Vice President


                                        CAPSTAR BROADCASTING CORPORATION


                                        By: /s/ Kathy Archer
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                                           Name:  Kathy Archer
                                           Title: Vice President

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