In article , Colin Green
wrote:
Thanks Jim

The tarnishing is something I'd considered, hence the use of Pro Gold.

If the effect keeps reappearing as quickly as you say and *is* due to
tarnish, then there is a significant fault/problem with the system
somewhere. If so, it would need investigating.

Of course it may be that my hearing is deficient in some way! In that
case perhaps I should see a doctor :-)

Nope. There should be be no need. I see no reason from what you've said to
say your hearing is 'deficient' - if by that you mean worse than is usual
for humans with good hearing. I'd assume your hearing is 'normal' or
better. :-)

Of course, if you *do* have a hearing problem then *hearing* the doctor may
be more important than seeing one... ;-

The problem is that all humans have hearing/perception systems where the
behaviour varies with time and with various external factors. Changes from
morning to night, changes when excited or bored, changes when you've
already spent ten minutes listening to music, etc, etc.

Also there are all sorts of other effects, so slight changes can occur due
to changes in humidity. air pressure, etc, etc.

So the changes you percieve may be due to normal hearing variations, or to
other effects. Can't say.

Slainte,

Jim

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