Austen wrote:
On Feb 5, 11:21 am, spamtrap1888 wrote:
On Feb 5, 7:43 am, Austen wrote:
If the buzzing is caused by something in the device itself, I would
check for faulty capacitors.

OK: We rarely use sound on this: I suppose I can just stick a plug in
the earphone socket. Are there any more widespread consequences to
leaky caps on a unit like this please? Would they prevent the unit
charging its battery? I suspected that no one would think that a
short in the battery would be causing the buzzing!

The stability of the sound circuit could depend on the battery having a low
impedance and acting like a capacitor. This would save on the need to have
extra capacitors included in the design. Then if the battery has too much
internal resistance this effect would be lost leading to parasitic
oscillations - buzz. I hope this gives you some confidence that a new
battery could cure the problem. But don't blame me if not...

Mike.
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