I've been considering the following at the moment:
1) Asus Xonar DX
2) Creative Soundblaster Z
3) Fiio E7/E10/E17
4) Schiit Modi
I require the following features:
1) It must be compatible with Linux
2) It must be compatible with the Equalizer APO program (http://sourceforge.net/projects/equalizerapo/) when using Windows
I do a little gaming, but not a whole lot, so I don't really require any fancy EAX/Dolby/5.1/whatever stuff that a gaming/movie soundcard would normally offer.
Trouble is, I'm not sure what would suffice as a problem-free replacement.
I'm tempted to go with the Xonar, but I'm a little put off by the "fluctuating volume problem" pointed out on the "Known problems" site for the Xonar unified drivers. The external DAC offerings might be nice, but they seem somewhat limited on output options. I'd like to be able to have sound output to my speakers by default and then have the device switch to headphone output when phones are plugged in (just as I do with the onboard now).
The Soundblaster Z might be what I'm looking for, but I don't know how driver support is compared to the Xonar, and I don't know how the how the sound quality compares to everything else I've mentioned.
Any ideas? Thanks.