This isn't new. Try the silicone spray anyway. It will "grease" up the track so that the window doesn't bind up in the first place. Unless of course it's so bad that you actually have part of the track loose, but that is, IMO, unlikely. When they start getting sticky (needing the silicone spray), they will start shifting and vibrating in the track until they will then act as you describe.

Look at it this way - a can of silicone spray is a simple and cheap fix. Isn't it worth at least a try to see if it will work before you take the panel off and start that mess? If it's as you describe, I'll bet that it will. Like I said, it's at least worth a try first. Maybe it will work, maybe it won't. Won't cost much to try it first!

-G