Loss of sound after recording

[crystalball]

Hi there

I installed the beta version on my new Vista-running laptop and recorded a few tracks off a vinyl record. The recording went well as did the conversion but as soon as this was done the computer lost the sound. Everything looks as if it's working but there's no sound coming out of the speakers. I restarted, everything was working properly again, but when I tried the process on audacity again the sound was lost once more. Has anyone encountered this problem before?

Thanks for your help.