video/audio playback kaput...!

[pinpointte]

hello
im in the process of trying revive my computer (hp pavillion dv5000 2.0ghz, 2gbram 120gb HD)
after a very odd meltdown that happened a month ago.
I have an external mixer, that i plugged in one night (USB) to record some stuff, and since then
the computer has been a total mess.
ive run every spyware, virus program and things are better and almost as quick as they used to be, but i think its more than malware...some weird frankenstein thing happened that night with the mixer.
thats why im here.

one of the main issues im having is that the audio and video are VERy glitchy these days.
any youtube video, or normal .mov .avi playback glitches in a pattern.
(smooth for 3 seconds, then GliTch, smooth, glItTch!, etc)
same with the audio. or it just doesnt synch up at all.
Ill list what ive tried so far below.
if anyone has any ideas please let me know
thanks!

:::::
-defrag
-virus removal, spyware, adware etc
-run in safe mode, same problems
-uninstalled video and audio codecs, and let windows reinstall on startup. (not sure if i did this right though, someone told me this might work at hp support)
-thats it.

please help!
or help to lead me in the right direction

thank you

[Forum Troll]

Go into your control panel and look at the audio devices. Then click the advanced button under the sound playback device, then click the performance tab. Adjust the hardware acceleration slider until you get smooth playback.

[Krispy Kritter]

These types of issues are usually driver related (especially noting the use of an external audio device). Uninstall the drivers and software for the external device and then try downloading and installing the latest audio/sound card drivers for your system.

If you are wanting to spend a little time, it may be worth the effort to also install the latest motherboard and video drivers.