The other day I went to roll down my passenger side window and it made a nice clunk, followed by many more clunks on its way back up. When I roll it down, its as though something is lop-sided inside. it will roll down a bit, studder, roll down some more, studder, and clunks here and there at any random point in time. When I took the door panel off I could not see anything out of the ordinary, so I assume it is my regulator, but that doesn't really explain the clunks..

-this is an aftermarket power window system. My car came with Manual windows.
-no I don't know where the work was done, but I'm sure I can find it in the receipts I have.
-regulators have been replaced once before. I remember reading that in one of the receipts. I believe it cost somewhere around 235 bucks.

any help?

alot of the time you'll have a roller that breaks and the clunk you hear is actually the lil metal pin the roller rolls on hitting the slide on the metal guide attached to the glass and which explains the clunk and the fact its not aligning up correctly either that or it has come off track orrrr the motor connection that opperates it has broken teeth you might need a little closer investigation of the situation remove the side panel and observe its opperation you'll likely find the culprate
good luck!