I'm just curious as to what causes AVR's to make clicking noises when:
1. They turn on
2. A few seconds after they turn on, and then sound and video are output.
3. Sometimes changing sound modes from Surround to Stereo for example.
4. Muting and un-muting.
Why do they do this, and what physically inside the units creates the 'click'? There's obviously a physical movement inside them that creates the noise, correct?