Volume issue - Doppelganger (AlanP v1.4 pcb)

[Strategy]

I had passed my Doppelganger (AlanP's v1.4 pcb) off to a family member and got it back with a strange issue. It's EXTREMELY quiet. At first I thought it wasn't passing signal but if I plug it into my mixing desk and push the gain up I can hear it is phasing beautifully. Just the whole thing extremely quiet. I have so far:
- replaced op amps
- checked continuity on all wiring
- reflowed some dodgy looking solder joints
Any thoughts on where gain might get sucked away in this circuit/culprit parts? I'm not the world's best troubleshooter so any help is HUGELY appreciated
I'd forgotten how good this sounds and would be excited to get it ironed out.
Thanks,
Strategy

[LaceSensor]

Sounds like a dodgy ground somewhere perhaps.

Check the footswitch for bypass.

check the spectral/true bypass

check the blend pot. It should act as a volume control in Vibrato mode, and a Blend control in Phase mode.

[Strategy]

Thanks! I'll try these
Strategy

[Strategy]

Well: still super quiet
- Checked all grounds for continuity
- Tested footswitch
- Tested phase/vibrato switch
When this switch is set to Vibrato, I get nothing. No signal. So that might be a clue. Additional advice appreciated!
If I find the fault is in my offboard wiring I'll let this be a reminder to myself that this is what I get when I veer off from the project as designed...
Strategy

[alanp]

Any photos?

[Strategy]

I'll take some and post later today!

[Strategy]

OK here's some images; was wrestling with image posting. Note that I ran out of TL074's so used TLV274's, which seem to work fine - it does phase, and the LFOs work great, and the only control that doesn't seem to work is the Vib/Phase switch. I just have to crank up the volume on my mixing desk to hear it. But I have some TL074's on order in case that's an issue. The low output issue happens with the TL074s as well as with TLV274s.

[alanp]

Oh man, I forgot how embarassing my early boards were!

Nothing leaps out at me, sorry