Hi all,
I've recently purchased a second-hand Moon Phase stereo filter. It seems to not working properly, but I'd like to see if I can fix this issue myself first :).

The module was a DIY kit, which, according to the docs, doesn't have a whole lot which you need to solder. LEDs, jacks, potmeters and one big button in the middle. Fairly straight-forward, all SMD parts are pre-soldered. So logicially I'd think if it doesn't work properly, it's somewhere in there parts.

The issue is as follows:
The left audio channel works as expected. Filter opens and closes and has the desired effect on the incoming audio. However, the right audio channel doesn't have any resonance on it. The difference is quite audible when I put the filter mode select to both lowpass filters.

Also, probably related, when I have all the knobs at 12 o'clock and start turning up the stereo frequency control, the right audio channel pops at around 4 o'clock (so when it's around 80% open) and the audio seems to glitch out and gets heavily reduced in volume. This audio change doesn't sounds intentional (not like the low frequencies that are reduced on certain filter with a high resonance). It pops really hard (like a click sound) and then the sound get very noisy and high-pitched, it doesn't sound intentional at all.

I've messaged Patching Panda right away through their contact page but haven't got a reply yet, tried Instagram DM but no reply on that either (yet).
I've DIY'd modules in the past and have some electronic background. To me, it sounds like some signal path is short-circuit, as the right channel doesn't pass through the resonance, but I'm not sure.

Does anyone have an idea what can cause this and/or how to fix this?