I've acquired a used STRYMON / IRIDIUM amp and IR cabinet emulator. The GAIN and LEVEL knobs were deformed, so I replaced them with two BOURNS pots of the same specifications. The unit was originally functional, and after replacing the pots, there were no issues with the tonal changes caused by the knobs, nor with the inputs and outputs (input is TS mono and TRS stereo, output is L mono and LR stereo). I haven't used the EXP/MIDI and USB functions.