Does anyone have the "microphonic" problem I described? When I plug/unplug my T1 into the 1/4" jack, I get a sound like a mike is being disconnected while the PA amp is on, a sort of hummy/thunky/staticky sound (more evident with the Bada; less evident--but still evident--with the DV336SE). I do not experience this phenomenon with either the DT880/600 or K501. Both are dead quiet when plugging/unplugging.
Possibly, this could be due to the third wire inside the T1 cable leading to each earcup. I presume that wire is there as a shield/drain of some sort, and that it's normally connected to ground. Perhaps during plug/unplug, it is momentarily acting as an antenna when it touches the L or R hot part of the jack. Whether or not such contact produces humming could be depending on the amp or ambient EMI.
Just speculating, of course.