What causes 'noisy' DVD tracking?

Is the disk actually playing correctly? It's possible to misload them and get some odd noises.

Usually, it is the lens suspension 'singing' that kicks up tracking noise. The focus and tracking motors are just coils that operate in a magnetic field to move the lens up and down (focus) and side to side (tracking) and are thus like a tiny 'loudspeaker'. If the lens is being driven by a 'scruffy' tracking or focus signal, the usual result is the audible whistle / hiss / grinding noise, which can be quite loud, but I would stop short of saying that I have ever heard it louder than the soundtrack, except where it is just quiet dialogue. The normal cause of a scruffy signal, is a marked, scuffed or scratched disc, but there are some automatic servo gain control faults that can cause similar symptoms. Have you checked any discs that are affected to make sure that they are clean / undamaged ? Are the same discs always affected in the same way ? When doing it, are they playing 'normally' in terms of picture and sound ?

It is also possible to get loading problems which can cause a disc to mechanically drag on the edge of the tray, and also to get partially collapsed deck suspension rubbers or springs, which can cause intermittent mechanical drag issues. Because DVD discs rotate at such high speed, even a slight drag makes a lot of noise, but will often allow the disc to play normally. If you can catch it doing it, and whip the lid off to take a look, it should be obvious if it is a mechanical issue, unless it's one of those machines that uses a computer-style drive, that's fully covered in ...

Arfa

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Thank you for your detailed reply.

It is a NEW never previously viewed DVD. It plays normally. But, I never verified proper loading. It has been ejected and reinserted with little change. I don't think I can get the lid off this unit easily.

From your description it would seem possible that the tracking on this machine is set in one operational norm and the tracking for 'general' DVD is somewhere else. So that when this machine plays such a standard disc the machine complains. Makes sense.

I guess the solution is to put the machnie in a box, in a cupboard, under a blanket. Except the remote then has difficulty.

Robert

Thank you for your detailed reply.

It is a NEW never previously viewed DVD. It plays normally. But, I never verified proper loading. It has been ejected and reinserted with little change. I don't think I can get the lid off this unit easily.

From your description it would seem possible that the tracking on this machine is set in one operational norm and the tracking for 'general' DVD is somewhere else. So that when this machine plays such a standard disc the machine complains. Makes sense.

I guess the solution is to put the machnie in a box, in a cupboard, under a blanket. Except the remote then has difficulty.

Robert

A new disc doing it would seem to eliminate surface damage as the cause, and the fact that any given disc which does it, continues to do it even after multiple re-load attempts, would probably eliminate mechanical issues due to misloading. Sometimes, you just never get to the bottom of what causes some discs to misbehave in some machines - it's just one of those things. Another slight possibility is that the boss in the centre of the turntable, might be right at the top of its moulding tolerance. If you then get a disc which has a hole right at the bottom of its size tolerance, you can get a situation where the disc will not sit quite flat on the turntable. This can cause the disc to run with a slight wobble which is enough to make it catch on the tray, but still within the limits of what the focus servo can handle, so it still plays ok.

Arfa