The Codec Tweak Tool option to "Fix broken sound" causes this problem. It does two things. (1) It sets HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Drivers32, 'aux' string value to "C:\Windows\System32\wdmaud.drv". I think 'aux' should
be set to "wdmaud.drv". (2) It creates a new, I believe unnecessary, string value named 'wdmaud.drv' set to "C:\Windows\System32\wdmaud.drv".
I am not sure how to contact the author of Codec Tweak Tool. Perhaps someone else will have better luck with that.
Wow thank you for pointing this out and everyone else who tested and gave their additions. I've been hacking online for the past 48 hrs for a solution to this, and it did fill my suspicions that it was related to applying the Codec Tweak Tool, was able to
use audio mixer from taskbar by switching the aux reg value back to wdmaud.drv.
If you don't mind sharing, how do you monitor registry changes made by a certain app, like the Codec Tweak Tool? I mean if it involves using another app, then it would help me self-troubleshoot a lot of these registry-related errors that pop up once in a
while. Otherwise, that is some fierce work.
Clayton, Australia