Audio system failed on update to Gutsy 7.10:

[thomas fisher]

PC  P4 D  on Intel D945Psn MB  with onboard Intel high definition audio.

System was up and running ok prior to upgrade on UbuntuStudio.  
Something got hammered but I'm not sure what.
I have looked through the /var/logs, but I'm  failing to find a fault.
Check of the BIOS setting indicates audio is activated. 

On a normal boot the audio is active at the login window. Now it is not. 
Which tells me the problem is in the core kernel load.

The UbuntuStudio was running on the 2.6.20-16 realtime kernel.
The upgrade is running on the 2.6.22-14 generic kernel.

I would appreciate any thoughts on what to try - and or - check.

Thanks
Tom