Tried to crank window down and felt a pop..

[Fbks_Cruiser]

Window lowered about 1/8” before I felt the pop and the the handle just spun freely. Window didn’t go down any further. (It was cold and the window seemed hard to lower). If I turn the handle to raise the window it spins a full rotation or so then something engages and the window goes back up that 1/8”. Try to lower and handle just spins.
I can feel some things moving inside the door when turning the crank and since it does go back up a bit I know it is not just the handle spinning on the regulator.

Maybe one of the rollers broke and came out of the track? You guys think I will need to replace the whole regulator? Won’t know for sure until I get into the door, just looking for ideas from someone who knows these doors better than I do.

Btw it is a 1972.