i got a response back from sennheiser. they are indeed long out of production, and the response i got basically told me that if i want a similar sound, i'm fucked - they don't make anything remotely like this model anymore, so i'm better off trying to get them fixed than replacing them.

he also explained that if i end up getting new ones, i want to focus on open back models. after doing a little googling, i think he's right - and i think that the fact that most of the headphones i've tried have been closed back might be the biggest sound degradation issue i've been unable to get over. that muffed sound seems to be defined by this difference. but that's going to cost me probably close to $300.

it's imperative, though. i can't do anything without headphones.

the pair i got back in january are just not useful for recording. even at the time, i remember wishing that i would have got a gift certificate or something. they turned out to be ok for the laptop. but they run on a battery that turns on a "noise reduction". batteries in headphones isn't a good idea at all. but, that's secondary to all the processing at the headphone stage. i need headphones with zero processing - clean reproduction. those ones are made for people that want to listen to mp3s on their cell phone, not people that are recording or mastering things.

...and when you turn off the battery they're just glorified ear buds. i'm going to try them though....