Tascam 244 pitch and volume issues

Recently the control belt stopped working (the guy that had it before me just used a rubber band and it snapped) so I decided to use the opportunity to service both belts. After closing up everything I got to testing it and it seemed to work well, but with some time I noticed the pitch started wobbling and slowing down, way past the knob's limit, and eventually just crawl to a stop. Now ff and rw work with no issues, but the tape won't play at all, I opened it again and also checked the idler weels, everything looks fine and I'm out of ideas for what the problem would be, any ideas?
Also, the volume on the first channel has always been way too high compared to the others, not sure if that's a calibration issue.