speaker voice + music sound distorted

[Guest]

I noticed that the voice & music sounds from speakers on a friend's pc sounds
slightly distorted when playing video (email wmv,eml attachments; youtube
videos; etc). I can understand voices + hear music but they sound like
they've been sucking Helium.
I tried the sound & hardware trouble shooting in Help. Sound, voicde
playback device: Realtek AC97 Audio. Settings = 'Full', 'Best'.
MIDI music playback='Microsoft GS wavetable SW Synth'. Not sure if the
sound was always like this. Is the only solution to find new sound driver or
replace older speakers ? Can someone suggest solutions? I apologize for
what could be a simple problem. Thanks.

 

[Guest]

quick note: on Sounds tab, sound scheme is blank ('No sounds', 'Windows
default') but Voice playback device listed as shown below. Normal Windows
system sounds also sound sl. distorted.

 

[Bob I]

Hearing the "chipmunks" indicates that the incorrect driver was applied
to the system for the sound card. It could be the result of someone
"updating" the drivers using windows update. Go to the sound card
properties in Device Manager and on the driver tab, Select "Rollback
driver".