So, a bit of a tale, but it started when my sound just went out yesterday. Master Volume was, despite my setting it to whatever level, reseting itself all the way to zero before my eyes. I also was unable to put the volume setting in the tray. Anyway, I installed the sndvol.exe back into the system 32 in my windows folder (thanks to this site I could find it) so one problem solved. Still seems to be solved. Anyway, the same problem was happening with my Master volume slider (the cd etc sliders were as always) sliding itself back to zero. So after ages of mucking around I decided to rollback my device to the last known original configuration that worked (as far as I was concerned both were with the Sigma Tel Audio driver, so Im not sure what I rolled back to). Anyway, it worked and I thought I was fine, went to bed. Woke up this morning, and the same Master Volume slider problem started again.......So I decided I would try to update the sound driver with one of the recommended Realtec drivers. This didnt work either. So I rolled back the driver again, and after a few applying and okaying some of the settings in the sound devices part of the control panel, it started working!!! Am I going to have to install and rollback a driver evertime I want to hear sound on my computer!! As far as I can remember I have not actually installed any new software on my computer for a while, and definitely not in the last few days, let alone last night. anyway, other info Sigma Tel Audio on a Dell Pentium M Inspiron 600m (768MB RAM if it matters) Current working, prone to not working installed driver is Sigma Tel C Major Audio This was the original sound driver that came when I got the computer and has served we okay for the last 3 years. Please, if I could have some help on how to fix this or if others have encountered the same weird problem before. Even the stop-gap measure of rolling back drivers doesnt work, and I have no computer sound!!! Please help :)