Just to add my two cents here, two things... I'm using a Thinkpad X230 with Fedora 17. Everything was working pretty good, but one of the updates caused sound

Just to add my two cents here, two things... I'm using a Thinkpad X230 with Fedora 17. Everything was working pretty good, but one of the updates caused sound from VLC to have a lot of static for the first 30 seconds or so after waking from suspend. But only VLC -- no other apps were affected. I reverted to an earlier kernel, problem went away. Seems this was fixed after a couple months on another kernel update (or combination of kernel and VLC update). Secondly -- I picked up a generic USB 5.1 sound card. All works well, except the center and subwoofer channels are switched. I've seen a few posts here and there on editing some PulseAudio configs, but they don't seem to apply to the version that Fedora 17 ships with. But the proper fix is to register this sound module in the "glitches" section of the appropriate Kernel driver, and have it swap the channel mappings there. Still working on finding which data structures the output channel maps are stored in -- if anyone here has worked with programming these kernel modules, let me know and I'll dig up where I left off.