audio / card recording issues

We are having a problem with recording clean audio during Webinars
and I thought I would post it up and see if we could get to the bottom
of it and get a recommendation on a sound card if that would fix the problem.

We do some live recordings and use Camtasia and Go To Meeting and
we get poor audio out of both recordings using a PC.

The audio recordings sounds compressed or "tinny" and I have been able
to isolate what is happening and I just need a way to fix it.

We use a
USB headset with a mic attached I don't believe the mic is the problem.

I did several tests on a Mac using various programs and the headset
seems to record a clean signal. I used FCP and another audio program and
I get a clean audio recording every time.

I have tried three different PC's and we get the same bad result on each
one.

The common denominator is that the computers use the on-board
audio recording capabilities through the mother board.

We could certainly put a sound card in one of the computers but I don't see any of the cards that have a USB input.


Any advice.