Experience (Foxx Tone Machine + Swell) - debug

[Strategy]

Here's a pedal I've been working on for a couple of years. I've gotten it working twice only to have subsequent failures without any obvious cause. It's a layout and schem (greenfuz? or philpot?) that I found using the Wayback Machine, but I see someone has posted it in the forum on this thread: http://www.diystompboxes.com/smfforum/index.php?topic=80966.0

Current status: I had it working perfectly, went to wire in an on-off switch for the battery and noticed that it was no longer working. Determined the error was somewhere in the wiring so I basically have re-done the wiring with extreme care. I do get functionality now, except one major issue: effect overall volume is extremely low compared to the input volume when bypassed. If I crank up my amp/mixer I can tell that the circuit sounds like the Experience I know and love, but it is really quiet.

Anyone familiar with this one and could tell me where in the circuit I might expect to find causes for this? I have checked for broken or questionable joints, gone over wiring again for errors, reviewed component polarity, etc.

Any suggestions appreciated!

STRATEGY