webcam mic stopped headset mic from working! eeek

Hi
I have a plantronics headset/mic
and it is wonderful. (it uses the jack).
Then I installed a lifecam 1000 USB... the mic seems to have over-written my headset mic.
I have tried everything to get the headset mic to work.

I have uninstalled the lifecam software still no luck.
Even in sound recorder I can't record anything.

I have a feeling that my comptuer is looking for the mic in the USB port.. and I don't know how to tell it to look for the jack.

Win xp sp2
onboard sound card (i know its the suxors) Using realtek drivers. (already updated and re-installed)

i've checked the mic in sound control and it should be activated.... but it's not.

Does anyone here have any ideas? and if you do.> thank you thank you thank you!

Duesy