Danelectro cool cat fuzz v2 troubleshooting

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Hi all, my first post, apologies if in the wrong place or inappropriate.

Can you help me with this pedal please?

Problem is it works fine on bypass, but when turned on, blue LED lights up, but no sound.
I've had a crack with the multimeter, the switch looks good, same with the dip switches and 5k trim pot.
This pedal has some internal LEDs that light when you adjust the dip switches. Noe of these light up.
Has anybody had any dealings with these that can kindly point me in the right direction?

Thanks in advance