E6400: no audio after playing flash vids in any browser

Hi, I have a Latitude E6400, running Win7, 32 bit.

Laptop just won't play any sound after I watch a couple of youtube vids on firefox or chrome. No audio, from vlc or volume controls or anything else.. though volume is not mute. Also no sound if I run a test from 'speakers properties' though all software controls show sound is ok and functional.

Any idea what's going on? Any help appreciated,
Thanks

 

Do you have the proper audio drivers installed? Have you tried booting into a Linux live disc and testing it out?

 

I've booted many linux livecds on this machine before. Sound works no problem. But why would I test a livecd ? Hardware works fine. As soon as I reboot the machine audio comes back normal.
As for drivers, I downloaded the drivers from dell.com .. that was about 5 months ago.
I also tried updating flash to the latest version..

 

The Linux live disc was to rule out hardware vs software. So if it works in Linux, you have a software issue. Perhaps something got corrupt with your drivers? Have you tried uninstalling them through device manager and reinstalling them?

 

well im sure i've done this before, but i did it again just to do it again .. works! installed driver again from here >> Drivers and Downloads | Dell [United States]

seems ok for now. plays vids and audio alternately .. no problem.
Thanks