I am running Vista. All sound worked fine before installing a Logitech Webcam. Since then, I cannot get audio from iTunes (internal or external speakers). System sounds and streaming audio (YouTube) work fine. I checked the drivers and they seem fine. I can see though device manager that the digital codec is working (the green EQ light is going up and down while iTunes is playing) but no audio. It is almost like something is muted, but I have checked everywhere.

i have my system speakers as the default audio device (if I switch it to the codec, the above audio stops working - not sure if that is normal or not).

Can anyone help??

Have you tried uninstalling Itunes and then reinstalling it!