Pedal PCB Expandora Clone Help - Forbidden Mode

[TySN_Sound]

Hello,

As the title suggests, I am currently building an Expandora Clone with a board from Pedal PCB.
Got it working, but when it's set to "Forbidden Mode" (only the Fet from the opto coupler in the feedback path) with the gain set to max and my guitar's volume set to max, it get super gated and ALL the high end is cut off.
Like there is a Low pass around 200 Hz or so and when I stop playing the signal is silent for a second after, then comes back like normal.
And when I back off the gain even a little, or my guitar's volume, it doesn't do this.
It's my first time using opto couplers and have never played an Expandora before, but none of the demos I hear sound like this (it sounds like the demos when the gain/gtr volume are down a little).

Any help would be appreciated!

Thanks!

[iainpunk]

i see we have another thread of the year nominee!!!!