If you've had to add leather ear pads for extra bass, then you bought the wrong headphones.
I've also got a pair of HD600's, but they aren't really the best choice for other media. They are music monitoring headphones and are not what you would call 'fun', which is really what you'd want in a pair of headphones for film/movie use.
I assume you have the Xonar set to 8 audio channels and use Dolby Headphone? That does help quite a bit with the HD600's, but it can only do so much really. I've also got a pair of Denon D2000's, and they are much better suited to film/movie use, with or without Dolby Headphone.
HD600's are fantastic headphones though, and for most music I listen to, they get more use than the Denon's, except maybe when it comes to electronic music. For other media though, the Denon's are superior.
If you already use 8 audio channels and Dolby Headphone, it's as good as you're going to get really, without buying another pair of headphones.
