SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

SCHEDULE 13D/A

(Amendment No. 4)

(Rule 13d-101)

Under the Securities Exchange Act of 1934

Affinity Gaming

(Name of Issuer)

Common Stock, $0.001 par value per share

(Title of Class of Securities)

Not Applicable

(CUSIP NUMBER)

Thomas Surgent, Chief Compliance Officer

Highland Capital Management, L.P.

300 Crescent Court, Suite 700

Dallas, Texas 75201

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

June 2, 2015

(Date of event which requires filing of this statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition which is the subject of this Schedule 13D, and is filing this schedule because of Rule 13d-1(e), 13d-1(f) or 13d-1(g) check the following box  x.

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934, as amended (the “Act”), or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act.

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AMENDMENT NO. 4 SCHEDULE 13D

This Amendment No. 4 (this “Amendment”) reflects changes to the information in Schedule 13D relating to the Common Stock of Affinity Gaming filed with the Securities and Exchange Commission (the “Commission”) on June 6, 2013 by the reporting persons (the “Original Schedule 13D”), as amended by Amendment No. 1 filed with the Commission on October 15, 2013 (“Amendment No. 1”), Amendment No. 2 filed with the Commission on December 5, 2013 (“Amendment No. 2”) and Amendment No. 3 filed with the Commission on July 31, 2014 (“Amendment No. 3” and, collectively with the Amendment No. 1, Amendment No. 2 and the Original Schedule 13D, the “Schedule 13D”). Each capitalized term used and not defined in this Amendment shall have the meaning assigned to such term in the Schedule 13D. Except as otherwise provided herein, each Item of the Schedule 13D remains unchanged.

Item 4 of the Schedule 13D is hereby supplemented to add the following:

Item 4. Purpose of the Transaction

The Reporting Persons entered into a certain Amendment No. 3 to the Stockholders Agreement (“Amendment No. 3 to the Stockholders Agreement”) with the Other Holders, dated as of June 2, 2015, which extends the term of the Stockholders Agreement to March 31, 2016 (unless earlier terminated pursuant to Section 4(b) of the Stockholders Agreement), and modifies certain restrictions on transfers of shares of Common Stock among the parties. All other terms and conditions of the Stockholders Agreement as disclosed on the Original 13D on June 6, 2013 remain in full force and effect without amendment. Amendment No. 3 to the Stockholders Agreement is filed herewith as Exhibit 99.6 and incorporated herein by reference.

Item 7 of the Schedule 13D is hereby amended to add the following:

Item 7. Material to be Filed as Exhibits

Exhibit 99.6 Amendment No. 3 to the Stockholders Agreement by and among SPH Manager, LLC, Spectrum Group Management, LLC, Highland Capital Management, L.P., One East Partners Opportunities, L.P. and One East Partners Master, L.P., dated as of June 2, 2015.

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Signatures

After reasonable inquiry and to the best of their knowledge and belief, each of the undersigned certifies that the information set forth in this statement is true, complete and correct.

Dated: June 3, 2015

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EXHIBIT 99.6

AMENDMENT NO. 3 TO THE STOCKHOLDERS AGREEMENT

This AMENDMENT NO. 3 (this “Amendment”) is made and entered into as of June 2, 2015, with reference to that certain Agreement, dated as of May 29, 2013 (the “Stockholders Agreement”), by and between each of the entities listed on Exhibit A thereto (each such entity and any other person who becomes bound by the Stockholders Agreement as contemplated by clause (a) of Section 1 thereof, a “Stockholder” and collectively, the “Stockholders”), as amended. Capitalized terms used herein and not otherwise defined shall have the meanings ascribed to such terms in the Stockholders Agreement.

WHEREAS, Courage Capital Management, LLC and its affiliates (“Courage”) sold all Shares owned by Courage in accordance with Section 1(c) of the Stockholders Agreement and Courage ceased to be a Stockholder;

WHEREAS, the remaining Stockholders wish to extend the term of the Stockholders Agreement;

NOW, THEREFORE, in consideration of the foregoing and for other good and valuable consideration, the receipt and sufficiency of which is acknowledged, and intending to be legally bound, the parties agree as follows:

1. Restrictions on Transfer. Section 1(c) of the Stockholders Agreement shall be amended and restated in its entirety as follows: “(c) such Transfer is unanimously approved by the holders of the Owned Shares held by Stockholders other than the proposed transferor; or (d) such Transfer is by either (i) Highland Capital Management LP, (ii) Spectrum Group Management, LLC or (iii) One East Partners Opportunities, L.P. and One East Partners Master, L.P., acting together (each, in such transferring capacity, “Transferring Owner”), representing a Transfer of all or a portion of the Owned Shares held by such Transferring Owner, to SPH Manager, LLC, after not less than five (5) business days’ notice of the proposed Transfer to each other Stockholder.”

2. Term and Termination.

(a) Section 4(a) of the Stockholders Agreement shall be amended and restated as follows: “Unless earlier terminated pursuant to paragraph (b) of Section 4, the term of the Agreement shall be a period expiring on March 31, 2016.”.

(b) Section 4(b)(1) of the Stockholders Agreement shall be amended and restated as follows: “(1) may be terminated with the unanimous approval of the holders of the Owned Shares held by all of the Stockholders bound by this Agreement by written notice to each other Stockholders delivered not less than two (2) business days prior to such termination;”.

3. Miscellaneous. Except for clauses (a), (d) and (l) thereof, Section 5 of the Stockholders Agreement is incorporated herein, mutatis mutandis.

4. Effectiveness. This Amendment shall be effective as of the date first written above by and among each Stockholder that has executed this Amendment as of such date.

5. Ratification. Except as specifically modified herein, all terms and conditions of the Stockholders Agreement are hereby ratified and confirmed in all respects and shall remain in full force and effect.

[Signature page follows.]

IN WITNESS WHEREOF, each of the parties has caused this Amendment to be duly executed as of the day and year written above.