Slight color picture distortion with Expansion Module #1

[motonerve]

I recently got an Expansion Module #1 and it's giving me some distortion in the picture while in color mode, while looking pretty clear in black and white. The picture for colecovision games looks clear and I'm outputting through Yurkie's composite mod, if that makes a difference.

I'm curious what course of action might be needed to resolve this. I noticed that there is adjustable potentiometer inside while cleaning, but I'm not sure what it does.

 

Here is a video of what it's doing. https://youtu.be/usGANOI4tnc