I use Audacity, a free PC Recording application. What it does is simply record to audio what ever you are sending to your PC speakers.
Dan, has anyone ever called you a walking library?
As it turns out I have attempted this with Audacity in the past and I think it messed up or disconnected my audio drivers. And I found that RealPlayer [usually] does this well with a small footprint on my other applications. These "RealPlayer gremlins" happen randomly and only on occasion. I'll guess that it's 95% reliable.
I sent Matt a snipett of the problem and will see if he comes up with anything. If not, I think I'll just re-download the video with RealPlayer again and I'm almost certain the portfolio of gremlins will be different and hopefully, non-existant.
My thinking behind posting this problem is it may be possible to "filter" the audio file in some way, perhaps with a low-pass filter or similar. I also thought that someone here might have a contact at the makers of RealPlayer that could shed some light or at least put this on their bug list, assuming RealPlayer is the problem.