Buteman, thanks. It's interesting you would follow that line of enquiry. One of the first things I did when the sound/video went 'wonky' was to uninstall Roxio and iTunes. I recalled, when I'd installed iTunes, that I got some weird message telling me that the iTunes CD/DVD writer drivers conflicted with writer drivers that had previously been installed, and that I needed to uninstall them. I reinstalled iTunes first, then Roxio, but that didn't solve the problem. I'll certainly take a look at that link, see if it gives me some new ideas. Thanks!