WMP 12 randomly stopped playing ac3 audio on .avi's

Hello

I just noticed today that when i try playing .avi's with ac3 audio, which usually pop up with a dolby digital logo on wmp have stopped playing. I get only the video and have tried a few things like turn off and on media features, as well as sfc/scannow (says no problems) nothing is making it work agian. The last time I played one of these files with success is 7/3/11. Today i turned on the P.C with the problem and let windows do a simple update, and updated ccleaner.

I don't think system restore will help.

anyone know whats wrong? Did some wmp reg audio key get deleted?

how to I uninstall wmp and reinstall it if i can?

soo yea, i just did a system restore to a date will im positive ac3 in avi files worked and it still doesn't

im guess its a lost registry key. One time my avi's thumbnails wouldn't pop up and i got a reg key for it from shark 007 dude and it worked. maybe it can be the same for this problem

realized i had an avi file with ac3 audio in my other P.C and it works as well as everything else...

what is the problem with my laptop

Which codec pack you using?, the ac3 audio how many channels does it use?.
is it all video with ac3 or just a 1 or 2?

I'm only using the divx mkv playback codec. I had coreavc a while ago though before i replaced it with the divx. It's only 2 files that i have on the P.C that have ac3 audio, 2channel. It used to show that dolby digital logo on the wmp playback but now it doesn't with no sound at all. On my other P.C i got a tester avi file and it works perfect logo and all.

note that the 2 files used to work with the mkv divx codec so it can't be that. I'm postivite i'm missing a reg key. I do remember deleting one reg key on ccleaner and not saving it.

first try, Uninstall any and all codec packs you have reboot then run ccleaner, download Klite mega codec pack or cccp and install only one of them try that.
If however you really have deleted one of the reg keys and only as a last resort you could try to uninstall and reinstall WMP, here are 2 links for you:
Uninstall/Reinstall Windows Media Player 12 In Windows 7
I know this is for down grading to 11 but if you install 11 you can then update to 12.
How To Uninstall Windows Media Player 12 on Windows 7?

I also dont have audio on avi files with AC3 audio but i can use powerdvd11 and it works just fine. i have no codec pack install but i swore it worked fine in the past. Other then installing a codec pack, any suggestions?