I have a 10 year old Apex TV, (CRT picture tube).

It has gradually acquired some irritating faults, but now has one that
is pretty much intolerable.

When the picture (i.e., the scene) gets dim or very dark, the audio
level drops, practically to inaudibility.

I presently have more time than money, and I think I would like to
repair this TV if it's possible.

Could this audio symptom be the result of failing capacitors? If so,
approximately how many capacitors might be involved, and what is a
guesstimate for the cost of these capacitors?

If the symptom is almost certainly due to some other cause, what might
it be?

Oh, the reason I would like to attempt the repair is that the picture is
still sharp, bright and contrasty.

Thanks.

--- Joe