>After upgrading to the latest version of Ubuntu, I noticed a couple of glitches with my audio and particularly in Flash video. Basically, Flash video would have no audio, and various applications would just stop producing sound altogether.
I happen to have an Acer laptop which has an Intel HD audio chipset in it. After doing some searches, I finally found the only solution that worked for me. I needed to manually update to the latest ALSA version. Ubuntu is two versions behind, and there have been several problems fixed with the Intel HD audio chipset in the latest version. Version 1.0.18 worked for me and fixed my problems. I have audio working again with Flash video as well as the other audio problems were fixed as well.
If you have similar issues, you might want to follow the instructions and run the script from here.
Hopefully, Ubuntu will update to 1.0.18 in the future as well as the more current versions of PulseAudio (which they are now minor versions behind 0.9.13 is the most current, Ubuntu comes with 0.9.10).