1) Nope, only when they're plugged in and the amp is turned off. Fun trivia, I can unplug them, shut the amp off, plug them in and it will happen to a lesser degree. Something to do with the caps maybe?
2) Only my AKG K601 and K702 that I can tell. Their dome shape seems to make them oddly susceptible.
3) A sucking noise then a mild "pop" when they return to shape -- not like any turn-off thump I'm used to, but I never had a headphone amp do that honestly.
What's bothering me is it's really crumpling the K702 diaphragm -- with their multi-layer design I'm not sure this crinkling is particularly good for them :|
Edited by Shike - 7/15/11 at 12:22am