So you want to ensure when you switch to effects mode full signal is getting into and out of the circuit
So I'd reflow your in and out wires and make sure they get a nice solder connection to the pads
Or if you have an audio probe check signal in on the main pcb in pad to see if it actually gets in at a decent level
Your in wire in particular doesn't look like it has much solder on either end
Try to push the wire through so the insulation sits flush to the board and snip off any excess bare wire on the other side
Flush like this
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