Hi-Fi Audio Track Dropout (JVC HR-S5000U)

[Nitrous456]

(If this was posted in the wrong category, I'm sorry, don't crucify me too bad )

Howdy.

New member here, wanted to show off my (crudely set up) main unit for playback. A JVC HR-S5000U I picked up off eBay for about 100 bucks, one of 4 VHS players I own so far.

So far it has served me well (minus the missing flaps beside the Power Button, and the Manual Tracking/Sharpness knob, however there is a peculiar issue I've noticed. Tapes with Hi-Fi Stereo during playback flip constantly between that and the Normal Linear track, to the point where I have to manually set it to Linear only. I've attempted both cleaning the heads on the drum, and adjusting the tracking during playback, thought the results have not changed much. I'm deducing that the cause might be due to either worn Hi-Fi audio heads, a bad tape (which I've already kind of ruled out, as the issue persists with multiple tapes I've tried, but still likely), or an electronic fault in the Hi-Fi audio circuitry. Still currently reading through the service manual I just received a day ago.

However, I would like additional input from other members as well to perhaps steer me in the right direction.

Have an image of said unit (and more) and video link showing the issue listed below:

[Attachment 78170 - Click to enlarge]
https://streamable.com/4eug55

[davexnet]

Have you tried making a fresh recording on that unit, and is the problem still extant there?

[Nitrous456]

Have you tried making a fresh recording on that unit, and is the problem still extant there?

I have not as of yet, I do have a few tapes I wouldn't mind recording over, plus more dedicated fresh S-VHS and SG T-120 blanks on the way.

(EDIT: It might just be a few bad tapes? I played back my near pristine copy of Scream, along with a few other movies earlier today and the Hi-Fi track was steady after a little adjustment on the manual tracking.)