window won't go down consistently - help

A help request pls. Sometimes, and without a known cause, the front passenger window either won't go down at all or smoothly. It sorta drops a little, then stops, drops a little more, etc., almost like its off a track.

Taken to dealer twice before, they tell me bs reasons like the window is tinted (bought it that way stock, so...) or the window is dirty so dirt gets trapped (really, I can think of several Hiluxs that never had issues in much dirtier environments than my garage...).

I've searched this forum and see fuse related issues. But that would mean complete failure, right? Further, sometimes the right front speaker gets real scratchy. Again, not always like a blown speaker. Related issue?

Other thoughts? Thanks for helping out.

 

I'd just peel the door panel off and have a look.

 

Water intrusion into the door panel or moisture build up is my guess.

 

Thanks all. Dealer said it wasn't covered under warranty, confirmed their impressions that it is tint or dirt related. But no other window has the issue, it's a garage queen at this point, etc. What a mess...

 

My windows are tinted and I don't have that issue.