Snow Leopard - No Output devices found - (Audio) Help?

Question

Folks
I just installed Snow Leopard on my Mac Mini which I use as my home media centre. It upgraded fine except for the lack of audio devices it now reports. Ive been combing forum threads but to no avail.
Appreciate any help or suggestions
Model Name: Mac mini
Model Identifier: Macmini1,1
Processor Name: Intel Core Duo
Processor Speed: 1.83 GHz
Number Of Processors: 1
Total Number Of Cores: 2
L2 Cache: 2 MB
Memory: 2 GB
Bus Speed: 667 MHz

Answer 1

Update:
Syetm profiler told me I had no sound device. I did the PRAM thing and the plist thing. no help.
I then pulled opened the mac up and checked to make sure the daugther boards were properly seated ... I was desperate.
When I rebooted the machine, it came up WITH SOUND. I dont think it was me opening the box as it could have also been me booting the machine up with no toslink f/o cable plugged into the output jack.
When the mini restarted I got the bing over the system speaker, and once the machine had started the audio worked perfectly and I plugged the cable back in.
Since the sound has been working I have lost it a couple of time since, particularly after using DVD player. this has ofetn happened as I think it gets tripped up when swthching between 5.1 audio out and normal output. Again this sorts itself out if rebooting with the output cable disconnected.
I hate these type of issues as it seems so erratic. Let me know if starting with the cable out sorts things out.