Kicker ZX 750.1 missing cap preamp board

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I have an old school kicker ZX 750.1 amp that is not passing audio. I’ve been taking a hard look at the preamp board and there is a missing SMD capacitor C79 that goes across pins 1 and 3 of an A393F op amp.

I was wondering if anyone knew what belongs there or a safe value to use there to see if this is what is causing the amp to not pass audio. Also, feeding in a strong signal will cause the amp to cycle in and out of protection.

I have the area of interest circled in the attached photo.

Thanks,

David
 

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Post a pic of the Main board overall and one close up of the driver stage. This amp appears to be a 2008 or later.

Check the usual rail voltages and the nine pins on the preamp board. Also check the Vdc around U14-LM311 and waveforms on Pins 3,4 and 11 of the same chip. Post your results and screenshots.
 
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