S2000 Triple Double Diamond Sound Issue

[RetiredCMC2002]

I admit it, I am a noob!  I just purchased this S2000, Triple Double Diamond $1.00 slot.  It works perfectly with the only exception that I only get sound from the right side speaker.  I've swapped the speaker cables and i will get sound from the left side when I do this, but only one side at a time.
The slot is in our family room for fun and entertainment, but would like to have sound from both speakers.  Some of the stuff I have read tell me that I may need a stereo card to make this happen.  I've uploaded a photo of what I believe is the sound card that is located in the round top of the slot.
While I am an IT Guy professionally, software is my thing.  While I know what a multi-meter is and how to spell it, I have no idea on how to use one.  So please be gentle and guide me through the process.
Thank you very much in advance for your help and support.

[RB]

You can use a  multimedia lite card with a sound simm on your mpu to get stereo sound or change the harness from that sound amp board you posted a picture of to a mono harness for sound from both top speakers. I posted a pic of the mono harness. Six wires into 4 pins. Yours should be 6 wires into 6 pins.

[RetiredCMC2002]

Thank you for the fast response!  Where can I obtain the wiring harness that you described?  Seem that could be a little less expensive than buying the multimedia lite car with the sound simm.

[RB]

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