I have a Panasonic PV-V4522 VCR. When playing factory recorded tapes
every 8 to 9 seconds the picture does a verticle roll (2 to 3 rolls)
other than that the picture is good.
TIA

Could be out of mechanical alignment slightly, like loose
guide posts, something bent in the tape path. Did it just
happen, all of a sudden, or gradually? Make sure the pinch
roller isn't shiny. May just be dirty. Clean (very gently), at
the bottom of the video head drum, right at where the tape
ends. Could even be bad capacitors in the power supply.
What's the model, & can you post a picture? Sky.

I read your post on another site, that had more info. The "tadpoles"
you see in the pix while playing back, MAY be bad video heads.