Amendment 1 to the Master Service Agreement Between Sanmina-SCI and Symmetricom, Inc.

Exhibit 10.28

[***] Certain information in this document has been omitted and filed separately with the Securities and Exchange Commission. Confidential treatment has been requested with respect to the omitted portions.

Amendment 1 to the Master Service Agreement

Between

Sanmina-SCI and Symmetricom, Inc.

This AMENDMENT 1 (“Amendment”) is made effective on May 16^th 2012 (“Effective Date”) by and between Sanmina-SCI Corporation, a Delaware corporation having its principal place of business at 2700 North First Street, San Jose, CA 95131, on behalf of itself and its affiliates and subsidiaries (“Sanmina-SCI”) and Symmetricom, Inc., a Delaware corporation having its principal place of business at 2300 Orchard Parkway, San Jose, CA 95131 on behalf of itself and its affiliates and subsidiaries (“Customer”). Customer and Sanmina-SCI are sometimes referred to herein as a “Party” and the “Parties”.

WHEREAS, Sanmina-SCI and Customer entered into a Manufacturing Service Agreement (“Agreement”) dated March 22, 2010;

WHEREAS, Sanmina-SCI and Customer entered into Addendum One, dated September 18, 2009, to add Prepaid Inventory Program ordering process and inventory management to the Agreement;

WHEREAS, Sanmina-SCI and Customer entered into Addendum Two, dated April 2, 2010, to add transition project management services to be provided by Sanmina-SCI in connection with the closure of Customer’s Puerto Rico facility;

WHEREAS, Sanmina-SCI and Customer desire to further amend certain terms in the Agreement;

NOW THEREFORE, in consideration of the foregoing premises and for other good and valuable consideration, the receipt and sufficiency of which is hereby expressly acknowledged, the Parties agree to amend the Agreement as follows:

Termination By Written Mutual Agreement. This Agreement may be terminated in writing by mutual written agreement of the Parties.

10.1        Termination for Cause. Either Party may terminate this Agreement or an Order hereunder upon a material breach by the other Party of any of the terms and conditions of this Agreement, if the Party in breach (i) fails to cure the breach of which it has been notified, within 30 days after written notice specifying such breach is given hereunder; or (ii) with respect to a breach that cannot be reasonably cured within a 30 day period, fails to commence reasonable and good faith attempts to cure the breach of which it has been notified within 30 days after written notice specifying such is given hereunder and thereafter fails to proceed with all reasonable diligence to substantially cure such breach or, the breach remains uncured 60 days after said notice.

Without limiting either Party’s right to terminate this Agreement for cause, either Party may terminate this Agreement in writing to the breaching Party upon numerous or repeated breaches by the breaching Party of this Agreement which collectively are material, if after receipt of notice, the breaching Party (i) develops a mutually acceptable corrective action plan to cure such breaches, and (ii) fails to diligently pursue or cure such breaches in accordance with the corrective action plan within 60 days of notice.

10.2        Termination for Convenience. Either Party shall have the right to terminate this Agreement, in whole or in part, for convenience upon one-hundred twenty (120) days written notice to the other Party. No later than the conclusion of the notification period, both Parties agree to finalize and implement a Migration Plan. Transfer of Products by Sanmina-SCI comprising greater than 50% of the then-current value of Orders and Forecasts to an alternate Sanmina-SCI facility without Customer’s prior written approval constitutes a termination for Convenience by Sanmina-SCI and is subject to the one-hundred twenty (120) written notice to Customer prior to any such transfer.

10.5        Migration Assistance.

In the event of termination of this Agreement, in whole or in part, for any reason, the Parties will jointly develop and mutually agree upon a migration plan (“Migration Plan”) providing for (i) the timely transfer by Sanmina-SCI of Customer-Furnished Items, resources, Components, Products, services and any other goods, material, information or other items necessary for proper performance of the manufacturing services provided by Sanmina-SCI under this Agreement, to a Customer-designated third party (or, if applicable, to Customer or a Customer Affiliate) using lowest cost, commercially reasonable modes of transportation, not to exceed 1) 2.0% of the standard cost of the active Inventory (“active” defined as Inventory with MRP demand in the following twelve (12) months per the Product Build-out Plan, plus any Component Inventory on-hand covering end-of-life requirements), and 2) the transportation cost of ancillary manufacturing and test equipment as defined in the Migration Plan; (ii) commercially reasonable training and assistance by Sanmina-SCI to Customer, Customer Affiliate or Customer designated third party on processes, know-how, use and operations of equipments, fixtures, machine programs and any other materials or items to enable Customer, Customer Affiliate, or designated third party to properly manufacture Customer Products as contemplated by Customer under this Agreement. (All training provided by Sanmina-SCI under this subsection shall be held at Sanmina-SCI’s facility(ies)) and (iii) completion of a Product build-out plan and/or plan to disposition Excess and Obsolete inventory. In addition to the Migration Plan, Sanmina-SCI shall return to Customer or Customer designated third party, all Customer owned property and equipments, whether provided by or acquired on behalf of Customer during the term of the Agreement, including but not limited to Customer-owned fixtures, test equipment, solder stencils, Customer specific test and machine program files ), Product quality, test and RMA data, Customer specific Product work instructions paid for by Customer, Product BOM’s, and any other mutually agreed assistance the Migration Plan shall be effective from the date termination notice is given and continue until 10.5 (i) and (ii) are successfully completed.

The terms and conditions of this Agreement shall continue to apply to all activities and the relationship between the Parties during the period of time the Migration Plan is in effect. The Migration Plan will include a process whereby upon completion of all deliverables, milestones and other obligations hereunder, the Parties will meet and exchange information and documentation sufficient for Customer to verify and confirm the successful and complete transfer and migration, consistent with such Migration Plan. Both Parties shall have a reasonable time to correct any aspects of the Migration Plan that have not been fully, properly and accurately completed. Once the Migration Plan has been successfully completed, as confirmed by the foregoing process, each Party will confirm completion in writing to the other Party and neither Party will have further performance responsibilities or obligations under such Migration Plan thereafter.

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10.5.1        Migration Fees. Except as provided in Section 10.5.2 below, Customer shall only be charged (i) for additional resources used by Sanmina-SCI in providing the migration assistance, and (ii) any other additional resources mutually agreed to between the Parties, that would be used in providing the migration assistance. Shipping terms for transferred items in support of the Migration Plan shall be Ex Works Sanmina-SCI facility (Incoterms 2010). All services, assistance and support pursuant to the Migration Plan shall be provided at the lower of Sanmina-SCI’s then-current rates, or at the lowest available discounted rates applicable to other Sanmina-SCI’s customers with substantially similar volumes of business as Customer (“Migration Fee”). Customer shall pay the Migration Fee monthly, unless another payment schedule has been agreed in the Migration Plan.

10.5.2        If this Agreement is terminated by Sanmina-SCI for convenience or by Customer for a material breach by Sanmina-SCI, Sanmina-SCI shall provide Customer with the migration services and assistance as outlined in this Section 10.5 until completion of such transfer and migration at no charge, cost or expense to Customer beyond those liabilities related to meeting obligations under the Agreement. Migration assistance shall be conducted by Sanmina-SCI with minimal downtime and impact to Customer’s business and Customer’s customers.

Procedure Upon Termination. In the event of termination of this Agreement, Sanmina-SCI shall, without additional charge to Customer (i) stop performance applicable to said termination immediately or as described in the Migration Plan, (ii) promptly, or consistent with the Migration Plan, provide to Customer all Customer-owned data files; (iii) promptly, or consistent with the Migration Plan, return to Customer all Confidential Information, all Customer-Furnished Items in Sanmina’s possession or under its control and all copies thereof and any other items or supplies in Sanmina’s possession or under its control which are labeled or marked with Customer’s names, trademarks, or service marks, which were paid for or provided by Customer.

In no event shall Customer’s payment to Sanmina-SCI under Section 10.4 constitute a waiver by Customer of any kind to enforce any of the provisions of this Agreement or pursue any rights, remedies or options available at law, equity or otherwise.

Survival of Obligations. All rights and obligations under this Agreement or an Order which by their nature or meaning would survive and continue beyond any cancellation, termination or expiration of this Agreement or any Order shall survive such cancellation, termination or expiration of this Agreement or an Order.

Sanmina-SCI shall use reasonable commercial efforts to provide Customer with 3PL services in accordance with Exhibit F, which is hereby incorporated by reference.

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The Agreement together with the Addenda and this Amendment 1, constitute the entire agreement between the Parties hereto with respect to the subject matter hereof, and supersede all prior or contemporaneous agreements, representations, warranties, statements, promises and undertakings, whether oral or written. In the event of a conflict between the terms and conditions of this Amendment and the terms of the Agreement with respect to the subject matter hereof, the terms of this Amendment shall control. Except as specifically amended by this Amendment 1, all of the provisions of the Agreement shall remain in full force and effect and be binding upon the Parties hereto. This Amendment 1 and Agreement may not be amended, altered or modified except by a writing signed by both.

IN WITNESS WHEREOF, the Parties hereto have caused this Amendment to be executed as of the Effective Date, by their duly authorized officers.

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EXHIBIT E

Sanmina-SCI Derry/Manchester Cost Reduction Plan

•  This run rate will include all Sanmina-SCI sites.

[***] Certain information in this document has been omitted and filed separately with the Securities and Exchange Commission. Confidential treatment has been requested with respect to the omitted portions.

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EXHIBIT F

Service Level Agreement for Third Party Logistic (“3PL”)

Sanmina-SCI shall to provide Customer with 3PL services in accordance with the following terms:

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[***] Certain information in this document has been omitted and filed separately with the Securities and Exchange Commission. Confidential treatment has been requested with respect to the omitted portions.

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