Just a reminder that I've completed the test you recommended and could definitely still use your help with debugging this. I'm using a raspberry pi 4, with Raspbian OS 10 (buster), with the 6 channel input board attached to the input header and the 8 channel output board attached to the output header. The contents of my asound.conf, config.txt, and .asoundrc are attached to this email. The results of the test are that when looking at the Pi with the input on the right and output on the left, only the front 4 or 5 input pins gave any signal when running my finger along them. Thanks for any help you can provide!

CW