Shruti odd issue

My shruti-1 is suddenly behaving oddly. No audio out. But I do get normal audio out (low level) on the audio in jack, but nothing (no hiss even) on audio out. Version0.59, reloaded the os., everything on the menu runs fine and does what it is supposed to, except this. the filter knob and resonance does not do anything to the audio leaking out the in. Everything else works, shifting osc type, seq, lfo, seq etc. All I can think is maybe I plugged in the polarity voltage. Had a close look around, no obvious wire or cable issues, even odder as the jacks are self contained and well sodlered into the PCB. Now this is teh bamboo one with a volume knob on teh back, but I thought it was for incoming volume. Its quite odd and I suspect once AI start measuring volumes I’ll find teh Voltages are all fine or none of the rest including led and display circuit are running fine. Dead CEM 3379? Something dead on theVCA end or a weird ground thing? Honestly I am dubious that there was any significant trauma to teh circuit and its been running fine.

This reminds me of a problem 1.6.4 had. It was a fried op-amp.

op-amp, I’ll go there thanks.