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                                                                  EXHIBIT 10.4.2



                                  AMENDMENT TO

             DATA TRANSLATION, INC. DOUBLE SHELTERED RETIREMENT PLAN

Pursuant to Section 8.1 of the Data Translation, Inc. Double Sheltered
Retirement Plan, the following amendments are made, effective December 2, 1996:

1.   Section 1.15, shall be deleted in its entirety and replaced with the
     following:

"1.15     "Employer" means Media 100 Inc. and any Participating Employer, as 
          defined in Section 10.1, which shall adopt this Plan; any successor
          which shall maintain this Plan; and any predecessor which has
          maintained this Plan. The Employer is a corporation, with principal
          offices in the Commonwealth of Massachusetts."

2.   In Section 1.45, after the first sentence add the following sentence:

          "Effective December 2, 1996, the Plan shall be referred to as the
          Media 100 Inc. Double Sheltered Retirement Plan."

3.   Add a new Article X as follows:


                                   "ARTICLE X
                             PARTICIPATING EMPLOYERS

10.1  ADOPTION BY OTHER EMPLOYERS

          Notwithstanding anything herein to the contrary, with the consent of
          the Employer and Trustee, any other corporation or entity, whether an
          affiliate or subsidiary or not, may adopt this Plan and all of the
          provisions hereof, and participate herein and be known as a
          Participating Employer, by a properly executed document evidencing
          said intent and will of such Participating Employer.

10.2  REQUIREMENTS OF PARTICIPATING EMPLOYERS

          (a) Each such Participating Employer shall be required to use the same
          Trustee as provided in this Plan.

          (b) The Trustee may, but shall not be required to, commingle, hold and
          invest as one Trust Fund all contributions made by Participating
          Employers, as well as all increments thereof. However, the assets of
          the Plan shall, on an ongoing basis, be available to pay benefits to
          all Participants and Beneficiaries under the Plan without regard to
          the Employer or Participating Employer who contributed such assets.

          (c) The transfer of any Participant from or to an Employer
          participating in this Plan, whether he be an Employee of the Employer
          or a Participating Employer, shall not affect such Participant's
          rights under the Plan, and all 




                                      
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          amounts credited to such Participant's Combined Account as well as his
          accumulated service time with the transferor or predecessor, and his
          length of participation in the Plan, shall continue to his credit.

          (d) All rights and values forfeited by termination of employment shall
          inure only to the benefit of the Participants of the Employer or
          Participating Employer by which the forfeiting Participant was
          employed.

          (e) Any expenses of the Trust which are to be paid by the Employer or
          borne by the Trust Fund shall be paid by each Participating Employer
          in the same proportion that the total amount standing to the credit of
          all Participants employed by such Employer bears to the total standing
          to the credit of all Participants.

10.3  DESIGNATION OF AGENT

          Each Participating Employer shall be deemed to be a party to this
          Plan; provided, however, that with respect to all of its relations
          with the Trustee and Administrator for the purpose of this Plan, each
          Participating Employer shall be deemed to have designated irrevocably
          the Employer as its agent. Unless the context of the Plan clearly
          indicates the contrary, the word "Employer" shall be deemed to include
          each Participating Employer as related to its adoption of the Plan.

10.4  EMPLOYEE TRANSFERS

          It is anticipated that an Employee may be transferred between
          Participating Employers, and in the event of any such transfer, the
          Employee involved shall carry with him his accumulated service and
          eligibility. No such transfer shall effect a termination of employment
          hereunder, and the Participating Employer to which the Employee is
          transferred shall thereupon become obligated hereunder with respect to
          such Employee in the same manner as was the Participating Employer
          from whom the Employee was transferred.

10.5  PARTICIPATING EMPLOYER'S CONTRIBUTION

          All contributions made by a Participating Employer, as provided for in
          this Plan, shall be determined separately by each Participating
          Employer, and shall be allocated only among the Participants eligible
          to share of the Employer or Participating Employer making the
          contribution. On the basis of the information furnished by the
          Administrator, the Trustee shall keep separate books and records
          concerning the affairs of each Participating Employer hereunder and as
          to the accounts and credits of the Employees of each Participating
          Employer.

          The Trustee may, but need not, register Contracts so as to evidence
          that a particular Participating Employer is the interested Employer
          hereunder, but in the event of an Employee transfer from one
          Participating Employer 




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          to another, the employing Employer shall immediately notify the
          Trustee thereof.

10.6  AMENDMENT

          Amendment of this Plan by the Employer at any time when there shall be
          a Participating Employer hereunder shall only be by the written action
          of each and every Participating Employer and with the consent of the
          Trustee where such consent is necessary in accordance with the terms
          of this Plan.

10.7  DISCONTINUANCE OF PARTICIPATION

          Any Participating Employer shall be permitted to discontinue or revoke
          its participation in the Plan. At the time of any such discontinuance
          or revocation, satisfactory evidence thereof and of any applicable
          conditions imposed shall be delivered to the Trustee. The Trustee
          shall thereafter transfer, deliver and assign Contracts and other
          Trust Fund assets allocable to the Participants of such Participating
          Employer to such new Trustee as shall have been designated by such
          Participating Employer, in the event that it has established a
          separate pension plan for its Employees, provided however, that no
          such transfer shall be made if the result is the elimination or
          reduction of any "Section 411(d)(6) protected benefits" in accordance
          with Section 8.1(c). If no successor is designated, the Trustee shall
          retain such assets for the Employees of said Participating Employer
          pursuant to the provisions of Article VII hereof. In no such event
          shall any part of the corpus or income of the Trust as it relates to
          such Participating Employer be used for or diverted to purposes other
          than for the exclusive benefit of the Employees of such Participating
          Employer.

10.8  ADMINISTRATOR'S AUTHORITY

          The Administrator shall have authority to make any and all necessary
          rules or regulations, binding upon all Participating Employers and all
          Participants, to effectuate the purpose of this Article."

The Employer consents to and approves the foregoing amendment.

Except as herein amended, the Plan is ratified and confirmed.



MEDIA 100 INC.



BY:  /s/ Peter J. Rice                           WITNESS: /s/ Craig Barrows
     -----------------------------                        ----------------------

               12/2/96                                            12/2/96
     -----------------------------                        ----------------------
               DATE                                               DATE








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