Sometimes does not flip to side B. Is it time for a belt change or should I just open it up and clean it up a bit and put back together again and hope it works like I've done in the past. I've probably was able to play 50 or something movies before it messed up again. And this time it was probably my fault because i stopped it near the end of side B and this is when it started malfunctioning again.

If the belt has never been changed, it’s due for one.

Stop constantly cleaning what doesn’t need cleaning and do it right for a change (we’ve discussed this before).

Just cleaned the spindle carefully without overdoing it and it's back to working. I'm not sure if that has anything to do with it or not. Well, I'm assuming something like that was making it sound rough noise wise. Now it sounds good. All I have to do now is put the Wooden Panels back on it. I also carefully touched up what I think the belt is but if it is the belt someone probably replaced it already because it's grey looking and not a black belt unless this is something else. When I messed it up earlier I stopped it instead of letting the player finish the stop at the side of B. Something I did caused it to react negatively which started giving me P0 or PO errors.

You most likely accelerated the loss of rubber from the grip ring on your spindle so I would consider replacing that too.