Exhibit 10.1

FOURTH AMENDMENT TO CREDIT AGREEMENT

THIS FOURTH AMENDMENT TO CREDIT AGREEMENT (this “Amendment”) is entered into as of December 14, 2011 by and among DYNAVOX SYSTEMS LLC, a Delaware limited liability company (“Borrower”), DYNAVOX INTERMEDIATE LLC, a Delaware limited liability company (“Holdings”), DynaVox Services Inc., a Delaware corporation (“Services”), Blink-Twice LLC, a Delaware limited liability company (“Blink-Twice”), Mayer-Johnson LLC, a Delaware limited liability company (“Mayer-Johnson”), DynaVox International Holdings Inc., a Delaware corporation (“International”), EYE RESPONSE TECHNOLOGIES, INC., a Virginia corporation (“ERT”; Borrower, Holdings, Services, Blink-Twice, Mayer-Johnson, International and ERT are collectively referred to herein as the “Credit Parties” and each individually as a “Credit Party”), GE BUSINESS FINANCIAL SERVICES INC. (in its individual capacity, “GE BFS”), as agent (in such capacity, together with its successors and assigns in such capacity, “Agent”) for the several financial institutions from time to time party to the Credit Agreement (collectively, the “Lenders” and each individually a “Lender”), and for itself as a Lender, and such Lenders signatory hereto.

W I T N E S S E T H:

WHEREAS, Borrower, Agent and the Lenders have entered into that certain Third Amended and Restated Credit Agreement dated as of June 23, 2008 (as amended, modified, restated or otherwise supplemented from time to time, the “Credit Agreement”);

WHEREAS, Borrower has requested that Agent and the Required Lenders amend the Credit Agreement in certain respects as set forth herein; and

WHEREAS, Agent and the Required Lenders are willing to make such amendments subject to the terms, conditions and other provisions hereof.

NOW, THEREFORE, in consideration of the mutual agreements, provisions and covenants contained herein, the parties agree as follows:

I. Defined Terms. Capitalized terms used but not defined herein shall have the meanings ascribed to them in the Credit Agreement (as amended hereby).

II. Amendment. Subject to the conditions set forth below, and in reliance upon the representations and warranties of the Credit Parties set forth in the Credit Agreement and in this Amendment, the Credit Agreement is hereby amended as follows:

(1) Section 5.4 of the Credit Agreement is hereby amended by (i) deleting the word “and” at the end of each of clause (e) thereof, (ii) deleting the “.” at the end of clause (f) thereof and substituting the phrase “; and” in lieu thereof and (iii) adding a new clause (g) thereto to read as follows:

“(g) purchases by Ultimate Holdings of shares of equity interests in Ultimate Holdings promptly after its receipt of such Restricted Distribution so long as (i) before and after giving effect to any such dividend or distribution for such purpose, no Event of Default shall have occurred and be continuing and (ii) such purchases or payments after December 14, 2011 do not exceed $5,000,000 in the aggregate.”

(2) Exhibit B to the Credit Agreement is deleted in its entirety and Exhibit A attached hereto is substituted in lieu thereof.

III. Conditions Precedent. The effectiveness of this Amendment is subject to the satisfaction of the following conditions precedent or concurrent:

(1) the execution and delivery of this Amendment by each of the Credit Parties, Agent and the Required Lenders;

(2) all representations and warranties by any Credit Party contained herein or in any other Financing Document shall be true and correct in all material respects on and as of the date hereof or, to the extent such representations and warranties expressly relate to an earlier date, on and as of such earlier date; and

(3) before and after giving effect hereto, no Default or Event of Default under the Credit Agreement shall have occurred and be continuing.

IV. Representations and Warranties. Each Credit Party, jointly and severally, hereby represents and warrants to Agent and each Lender as follows:

(1) The execution, delivery and performance by each Credit Party of this Amendment and each other document, agreement and instrument executed by such Credit Party in connection herewith are within its powers, have been duly authorized by all necessary action pursuant to its Organizational Documents, require no further action by or in respect of, or filing with, any governmental body, agency or official except for actions or filings, the failure with respect to which could not reasonably be expected to have a Material Adverse Effect, and do not violate, conflict with or cause a breach or a default under any provision of applicable law or regulation or of the Organizational Documents of any Credit Party or of any agreement, judgment, injunction, order, decree or other instrument binding upon it, except for such violations, conflicts, breaches or defaults as could not reasonably be expected to have a Material Adverse Effect;

(2) this Amendment and each other document, agreement and instrument executed by such Credit Party in connection herewith constitutes a valid and binding agreement or instrument of such Credit Party, enforceable against such Credit Party in accordance with its respective terms, subject to the effects of (i) insolvency, fraudulent conveyance, reorganization, moratorium and bankruptcy or other similar laws relating to or affecting creditors’ rights generally, (ii) general equitable principles (whether considered in a proceeding in equity or at law) and (iii) any implied covenant of good faith and fair dealing; and

(3) no Default or Event of Default exists.

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V. No Waiver. Except as expressly set forth herein, nothing contained herein shall be deemed to constitute a waiver of compliance with any term or condition contained in the Credit Agreement or any of the other Financing Documents or constitute a course of conduct or dealing among the parties. Except as expressly stated herein, (a) Agent and Lenders reserve all rights, privileges and remedies under the Financing Documents, and (b) the Credit Agreement and other Financing Documents remain unmodified and in full force and effect.

VI. References. Any reference to the Credit Agreement contained in any document, instrument or agreement executed in connection with the Credit Agreement, including, without limitation, any Financing Document, shall be deemed to be a reference to the Credit Agreement as modified by this Amendment. This Amendment shall be deemed to be a Financing Document.

VII. Counterparts. This Amendment may be executed and delivered via facsimile or other electronic transmission with the same force and effect as if an original were executed and may be executed by one or more of the parties to this Amendment and any number of separate counterparts, each of which when so executed, shall be deemed an original and all said counterparts when taken together shall be deemed to constitute but one and the same instrument.

VIII. Successors and Assigns. This Amendment shall be binding upon and inure to the benefit of Borrower and each other Credit Party and their successors and assigns and Agent and the Lenders and their successors and assigns.

IX. GOVERNING LAW. THIS AMENDMENT AND THE RIGHTS AND OBLIGATIONS OF THE PARTIES HERETO SHALL BE GOVERNED BY, AND CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAW OF THE STATE OF NEW YORK.

X. Severability. Wherever possible, each provision of this Amendment shall be interpreted in such manner as to be effective and valid under applicable law, but if any provision of this Amendment shall be prohibited by or invalid under such law, such provision shall be ineffective to the extent of such prohibition or invalidity without invalidating the remainder of such provision or the remaining provisions of this Amendment.

XI. Reaffirmation. Each of the Credit Parties as debtor, grantor, pledgor, guarantor, assignor, or in other any other similar capacity in which such Credit Party grants liens or security interests in its property or otherwise acts as accommodation party or guarantor, as the case may be, hereby: (i) ratifies and reaffirms all of its payment and performance obligations, contingent or otherwise, under each of the Financing Documents to which it is a party (after giving effect hereto) and (ii) to the extent such Credit Party granted liens on or security interests in any of its property pursuant to any such Financing Document as security for or otherwise guaranteed the Obligations under or with respect to the Financing Documents, ratifies and reaffirms such guarantee and grant of security interests and liens and confirms and agrees that such security interests and liens hereafter secure all of the Obligations. Each of the Credit Parties hereby consents to this Amendment and acknowledges that each of the Financing Documents remains in full force and effect and is hereby ratified and reaffirmed. Except as specifically provided hereunder, the execution of this Amendment shall not operate as a waiver of any right, power or remedy of Agent or the Lenders, constitute a waiver of any provision of any of the Financing Documents or serve to effect a novation of the Obligations.

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– Remainder of Page Intentionally Blank; Signature Page Follows –

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IN WITNESS WHEREOF, each of the undersigned has executed this Amendment as of the date set forth above.

Fourth Amendment to Credit Agreement

Fourth Amendment to Credit Agreement

IN WITNESS WHEREOF, each of the undersigned has executed this Amendment as of the date set forth above.

Fourth Amendment to Credit Agreement

IN WITNESS WHEREOF, each of the undersigned has executed this Amendment as of the date set forth above.

Fourth Amendment to Credit Agreement

IN WITNESS WHEREOF, each of the undersigned has executed this Amendment as of the date set forth above.

Fourth Amendment to Credit Agreement

IN WITNESS WHEREOF, each of the undersigned has executed this Amendment as of the date set forth above.

Fourth Amendment to Credit Agreement

Exhibit A

EXHIBIT B TO CREDIT AGREEMENT (COMPLIANCE CERTIFICATE)

COMPLIANCE CERTIFICATE

DYNAVOX SYSTEMS LLC

DATE:                     ,         

This certificate is given by                     , a Responsible Officer of DynaVox Systems LLC (“Borrower”), pursuant to Section 4.1(c) of that certain Third Amended and Restated Credit Agreement dated as of June 23, 2008 among Borrower, the Lenders from time to time party thereto and GE Business Financial Services Inc. (formerly known as Merrill Lynch Business Financial Services Inc.), as Agent for Lenders (as such agreement may have been amended, restated, supplemented or otherwise modified from time to time, the “Credit Agreement”). Capitalized terms used herein without definition shall have the meanings set forth in the Credit Agreement.

The undersigned Responsible Officer hereby certifies to Agent and Lenders that:

(a) the financial statements delivered with this certificate in accordance with Section 4.1(b) and/or 4.1(n) of the Credit Agreement fairly present in all material respects the results of operations and financial condition of Ultimate Holdings and its direct and indirect Subsidiaries as of the dates of such financial statements;

(b) I have reviewed the terms of the Credit Agreement and have made, or caused to be made under my supervision, a review in reasonable detail of the transactions and conditions of Borrower and the Subsidiaries during the accounting period covered by such financial statements;

(c) such review has not disclosed the existence during or at the end of such accounting period, and I have no knowledge of the existence as of the date hereof, of any condition or event that constitutes a Default or an Event of Default, except as set forth in Schedule 1 hereto, which includes a description of the nature and period of existence of such Default or an Event of Default and what action Borrower has taken, is undertaking and proposes to take with respect thereto; and

(d) to the extent that this Certificate is delivered with respect to the end of a fiscal quarter of Borrower, Borrower is in compliance with the covenants contained in Article VI of the Credit Agreement, as demonstrated by the calculation of such covenants below, except as set forth in Schedule 1 hereto.

IN WITNESS WHEREOF, the undersigned officer has executed and delivered this certificate this                     day

of                     ,    .

CAPITAL EXPENDITURES

(SECTION 6.1)

EBITDA

FIXED CHARGE COVERAGE RATIO

(SECTION 6.3)

NET SENIOR DEBT TO EBITDA RATIO

(Section 6.4)

NET TOTAL DEBT TO EBITDA RATIO

(SECTION 6.5)