I boot my Ubuntu CD (I don't install it) and see if the sound has issues. If it does I know it's a hardware issue.
Hi, I have an MDG Intel P4 system, 2.4GHz, 512MB RAM, Win XP HE 2002 SP3, with SigmaTel C-Major Audio and Legacy audio drivers.
Within the last few weeks the output quality of my music has deteriorated to the point where the music largely overrides the vocals, the foreground and background vocals are reversed so that you barely hear the lead vocals while the background vocals are easily heard, and at times there is a muffled or an echoey quality to the music. I've tried adjusting the volume controls, I've changed speaker sets (the ones I have now work fine on my brother's Xbox), and I've played some of my MP3s in Nero but they still sound terrible. I do not have the ctmp3.acm codec, so the problem doesn't seem to be related to that WMP issue.
I have the following codecs, in this sequence of priorty:
Windows Media Audio
Fraunhofer IIS MPEG Layer-3 Codec
imaadp32.acm
msadp.acm
msg711.acm
msgsm32.acm
tssoft32.acm
msg723.acm
Sipro Lab Telecom Audio Codec
Indeo audio software
Ihacm.acm
Messenger Audio Codec
Microsoft PCM Converter
I'm not sure which ones are important or what order they should be in, or if my problem is even codec related. I did try uninstalling my SigmaTel Audio driver, but the problem persists. I have yet to try a system restore.
Any suggestions on fixing this problem will be greatly appreciated.

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