VCR Playback Issues

[amer1337]

Unit: RCA VR501A

Current Issue:
Trying to playback VHS, plays back with garbled sound and video lines for a few seconds then goes to bluescreen, cycles between those two for a bit.
If i fast forward the video appears ok as it fast forwards.

Initially i was getting no noise or video just bluescreen/black with noise when it would try to play and go back to blue.
I tried cleaning heads/fiddling with the tape roller guides (maybe shouldnt have done this?)
I took the top of the head drum off and noticed some copper contact pads on the bottom had some dirt/oxidation on them. I lightly sanded with 2000 grit paper to clean them and hit with a qtip to wash away. Also qtipped inside the drum.

Seemed to help with some video, thinking maybe i need to do this again and clean it a bit more but im out of my depth here so im posting here for possible guidance.

[davexnet]

Unit: RCA VR501A

Current Issue:
Trying to playback VHS, plays back with garbled sound and video lines for a few seconds then goes to bluescreen, cycles between those two for a bit.
If i fast forward the video appears ok as it fast forwards.

Initially i was getting no noise or video just bluescreen/black with noise when it would try to play and go back to blue.
I tried cleaning heads/fiddling with the tape roller guides (maybe shouldnt have done this?)
I took the top of the head drum off and noticed some copper contact pads on the bottom had some dirt/oxidation on them. I lightly sanded with 2000 grit paper to clean them and hit with a qtip to wash away. Also qtipped inside the drum.

Seemed to help with some video, thinking maybe i need to do this again and clean it a bit more but im out of my depth here so im posting here for possible guidance.

It's usually caused by the stationary control track head near the pinch roller; cleaning this often helps.
Could also be caused by edge damage to the tape; open the flap and take a look
https://forum.videohelp.com/threads/398278-Vhs-to-DVD-problem#post2590988