F3 monitor issues & audio question

[Arcade-Projects]

I have the F3 multi and been trying to run it on an Astro City cabinet running a 15khz monitor. Most of the time I've tried this setup there's been no problem getting the image to sync but lately it's been really inconsistent on the same cabinet and monitor. The screen gets garbled and just won't sync at all after I tried restarting the cab, flashing different games, etc. Zero issues with this hardware when I run it on my HAS (via RGB to component to CRT TV) but I'd really prefer to play it on this cabinet instead. Am I just screwed due to the weird refresh rate of the F3? Should I try on different monitors/cabinets?

Also somewhat unrelated...is there anything special I need to do in order to enable stereo audio via S harness? It's all hooked up according to the published Taito pinout but no audio plays through that harness in game or in the test menu. Not really a deal breaker for me tho, the Jamma audio sounds really good as an alternative.

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