Couple of things.
The design of the "holes" in the headseat are part of its audio design.
There are two basic types of headphone...circumaural and supra-aural.
Check out this page, for a full run down of the two different types of designs.
http://richardbrice.net/headphones.htm
Essentially, with the air holes in the back, allowing the drivers to "breathe" this wouldbe refered to as a semi-circumaural design.
Another point of information...the orange cable not only carries the sub woofer data, but also the center channel data as well. And some soundcards may have the channels reversed (and most good ones actually have a check box in the options to reverse them should you need to). So you should consult a speaker test/setup routine on your soundcard to make sure that all of the connections are proper before going any further, with your testing. It could very well be that your weak center channel performance could be becuase of this issue.
But, after yovue tested and ruled that out. I believe your issues with your audio can be easily resolved with some re-EQing.
Most games that "claim" 5.1 are actually 4.1 and as such you would never notice the weak center channel.
WHere in a movie 90% of the main dialog comes through the center chanel speaker. And in the case od a concert DVD, the dialog is spread across the whole front soundstage, and relys heavily on the front mains, to give you that "in concert live" soundstage that fills the entire area, not just the focal point.
It could also be a result of the decoder you are useing to watch your DVD;s with. Some software decoers have some very poor center channel performance, and need to be bumped up through a tweak, in order to get it to work at the same level as the rest of the channels.
I would recemend setting all of the levels on the headset at just about their maximum level, and then turning down the ones that seem overpowering. And then adjusting the total volume at the headset. While leaving the PC's volume levels at a constant.
THe bad thing about DVD's, and general consumer audio as a whole. Is that nothing is set to a proper reference spec as its being encoded, and distributed. While in the mixing process, and the recording process, everything is set to a strict set of reference levels. But when it gets to the DVD...all bets are off. ANd the fluctuations in range between teh channels can swing my a large margin from DVD to DVD. So your probibly going to have to reset the levels for each piece of source material you audition.
Then again, it could be that the center channel drivers are very weak,a nd simply cant keep up.
).
