Rhodes Chroma Polaris

Hello Chroma Group!  Winter sucks!

I'm reaching out to see if anyone could help me identify a problem that Ive recently noticed with my Polaris 2. I'm not sure if heating would cause this, because it never seems to get that hot but i noticed last night after a few hours that the volume dropped significantly(80%?). this occurred with both high and low outputs.  the level jumped around a bit, and after letting it rest for about 20 minutes it started being a BOSS again. does anyone know why this would happen?  i have basic soldering skills, but I'm very weak when it comes to troubleshooting.

the other question i have isn't too impending, but how do identify voices that have gone out in my Polaris?  i know that two are out, but I'm not sure how to safely go about finding and replacing the voice chips (is it that simple?). I love my Polaris to death, and if anyone could save me a drive to Minneapolis to Good Guys Audio Repair I would be beyond thrilled.

Thanks much in advance,

ianb