Vox V847 Wah to Dunlop CryBaby GCB-95 conversion - Volume drop

[Error!]

Hey there,

I am struggling with another project:

I always wanted to create my own custom wah pedal, so I started by building up a classic CryBaby (GCB-95) circuit on a breadboard.
But instead of the "standard" Dunlop parts I used a HALO inductor and a 100k ICAR pot. Also I preplaced the circuits original input buffer with a generic OP amp (TL071) based one and added a 50k trim pot in series to R7 ("vocal mod"). The result sounded absolutely fantastic.

To make it all permanent, I simply used the PCB of my old V847 since it seemed to be identical for the most part. All the parts that differed from the GCB-95 were replaced and the input buffer alongside the "Power Supply" were added on a piece of vero board.

The resulting pedal does work - kind of: It does produce a wah effect when I move the foot pedal, but in comparison to (true) bypass the signal is way quieter.
I have read that a bad capacitor (C3) might cause this significant drop in volume, so I replaced it which unfortunately did not change anything.

Right now I have no idea what else might have gone wrong. I really hope to get this thing going, since the breadboard prototype sounded awesome.

Here's a pic of the inside of the pedal:



I am referring to the schematics on electrosmash.com:
https://www.electrosmash.com/crybaby-gcb-95
and
https://www.electrosmash.com/vox-v847-analysis


Thank you all very much in advance!

Error!

[PRR]

Test the "generic OP amp" and the Wah separately. Is this "buffer" alone passing full signal? Is the Wah alone passing signal well?

[Error!]

Thank you very much PRR!

Testing both parts of the circuit individually made it pretty easy to locate the problem (some swapped pins on the TL071).

Now everything is working as it should.

Thank you ever so much for your help!