Does it play under Media Player Classic? If yes, then go to the File menu, select Properties, click on the Details tab, and see what’s listed under Audio. Then we’ll know what audio codec it’s using, and should be able to troubleshoot further.

I’ve actually delved more into getting this going with certain things, and tweaked the registry keys a little further as well, in addition to getting MPC playing better under Vista than it currently does (in addition to resolving subtitle issues, etc).

So once I get my hands on RC2, I’ll be rewriting this post, or possibly make a new one with pretty pictures included, and try my best to ensure compatibility with RC1, 5728, and RC2 as well.

The basic fix to allow Media Center to play back MKV’s and other obscure formats is actually in two forms: Setting the perceived type registry key to video, and adding in the permissions section to allow Media Player to play back those files. It doesn’t matter what they’re associated to, what you call them, or how they’re interpreted by Windows Explorer - just as long as WMP11 is “permitted” to play them back, and Explorer “perceives” them as video files.

Fianlly, after 2 days of searching, I found a great explanation on how to do it!
I downloaded probably over 100 different files and went to hundreds of different sites to find how to play mkv and other files via windows media center. And here it is!!!

Thank you so much! Simple… perfect!

First, the thumbnail offset option doesn’t do dick. Explorer now uses other methods to obtain thumbnails from video files, so to disable them, you’re going to have to do that from Folder Options (found in the Control Panel under Appearance and Personalization, or from the Organize menu in any Explorer window). You can also get rid of the little icon to the side from your thumbnails as well from the same place, if you choose to keep the thumbnails.

Second, it’s best to install MPC via CCCP’s installer after all, otherwise Vista will bug the everliving shit out of you for daring to run an executable that you downloaded from some webpage. In regards to changing the file associations, this has to be done from Explorer by right clicking on the file in question, going to Open With, and selecting Choose Default Program… and going from there.

Third, having Nero’s video decoders (comes with the Nero Vision Express installer) installed will cause Media Center to shit bricks and crash whenever looking at most MKV files. It seems fine with MP4, and most of my other various formats.. but something about my MKV files makes it spit the dummy. I’m guessing it’s some kind of drama between Nero’s AAC audio decoder and VobSub within MKV’s. WMP and MPC have no problems with these files, and Explorer generates the thumbnails just fine as well.

In any case, I’ll most likely use it whenever dicking with Vista, and feel the need to post from there.. but I’ll mostly do it the old fashioned way - pure HTML from WordPress’s post page.