RIP to BT Garner of MindRec.com... He passed away early 2023 from health problems. BT was one of the top PCE homebrew developers and founder of the OG Turbo List, then PCECP.com. Condolences to family and friends.
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Topics - Jugbug

#1
I was wondering if anyone might be able to help me out, or at least narrow down my search.

I recently replaced all the caps in my US Duo and now the sound through the AV and headphone jacks is barely audible.  From what I can hear it sounds like left and right are at the same level, and all the different types of audio are being played.  The headphone volume dial also controls the volume a bit, from barely audible to... even less so.  There's also a noticeable speaker thump when I turn off the system, although I can't say if that's new or if I'm just overly paying attention to things now.

The system lost audio about 8 months ago which I quick fixed by replacing C604 and C610 (the two marked as post op-amp in D-lite's thread).  The system has been fine since then aside from some crackling that would go away after a few minutes.

There were quite a few bad caps, but everything cleaned up nicely for the most part, except for two spots where the cap fluid seeped along traces under the solder mask.  One was below C135, which is a fairly thick trace and seems to be ok.  The other was C612 which lifted the trace below it a bit when I removed it.  I wired the replacement cap's negative to C305's negative, and the positive to pin 8 of the M51131L chip above it.  I hope these are the correct points, as the black cloud left from the cap fluid makes it a little hard to distinguish the traces.

I've been checking traces and vias for continuity, particularly to/from 4558 chips, but so far haven't found any problems unless I overlooked something.  Any advice or suggestions would be appreciated.