I am running Ubuntu 10.04 on a Dell Mini 10 netbook.
This has worked brilliantly for 18 months +.

Several times when running Update Manager and a new kernel is installed the system loses sound. I have usually managed to solve the problem following advice from several sources - both try to fix alsa packages / drivers. Here are links:

Recently however after Update Manager added a new kernel, sound stopped working and nothing I have tried fixes it. I have tried booting using previous kernels (by pressing Shift key on startup) - no help.

I also tried booting to 12.04 from USB and even then the sound is not working.

Yes, I tried the obvious sound settings to make sure nothing was muted.

Any advice welcome...