Zardon, did you find the original foam ring that will replace the disintegrated stuff? I could not find them anywhere. My old pair looked the same when I opened them up, and I had to clean them as well.
Have you guys messed with the USB streaming method setting in the settings program. I changed mine from safe (default) to standard to try and get jplay/jriver from making strange noises once in awhile. Didn't help. Don't get the noises with the Hiface 1.
Wow, now misinformation from someone who owns one, weird. I think you chose your words wrong. Maybe you don't like the 2-channel presentation? I have a 2-channel room measured and it sounds like that room. It is most definitely "out of your head". Pretty sure the thing was designed primarily for recording professionals so they could take their studio anywhere and continue to mix. Home Theater is another use.
Kevin believes the bias is quite important for the HE90, so if you listened at the Stax bias, this may be a factor. I can tell you I have heard both on the T2 and I prefer the proper HE90 bias of 500. There is a difference. I assume the BHSE was biased at 580.