Troubleshooting two broken Micro Synthesizers

[Kevin Mitchell]

I had to make a new thread for this - so forgive me for more discussions on this effect. But I need some help. I now have two Micro Synthesizers (one older guitar version and one 90s bass version) on my bench to debug. I've been enduring some serious time constraints and haven't had much time to dig into it until this passed weekend.
Here's the latest schematic.

Lets start with the guitar one since it's in better shape. My observations show that the signal passes through the effect up to the last stage (A14) but disappears completely as soon as it hits pin 3. I've replaced the IC (this one has EH1048 - house brand CA3094) with a socket and tried several other CA3094 chips with the same result.

I figured the signal was being loaded down by R96/47k then R97/1K to gnd (these OTAs like small signals at the input) for the VCA/Attack Decay part of the circuit but the signal doesn't recover. Attack Delay seems to be the issue. If I turn up the amp you can make out the mixed signals coming through but it's not the signal post-filter - rather a subtle sound of what must be coming through the Attack Delay pot. As I understand that should be the controlled voltage that triggers the VCA. Before pin 3 of that OTA (at C29) I can observe the signal proving the trigger, filter sweep and 4 voices are working okay. Although it did narrow down the problem area it has only further stumped me on debugging this thing. If the filter and trigger appear to be working what's holding up the VCA sweep generator from doing it's thing? I must be overlooking something...

I've measured and tested many of the parts thinking a diode, transistor or cap could be bad but couldn't find anything obvious.

I'm aware of a small mod to replace a resistor with a trimpot to improve the Attack Delay but I doubt that'll fix my pedal though I may try that anyways. Once I get this one situated hopefully it'll help debug the bass Micro Synthesizer which is having trouble at the filter.

I'll post voltages this evening. I'm hoping explaining my observations alone would queue the more tech savvy folks to direct me further in the meantime.

Thanks guys. I know this isn't an easy one.
-KM