Audio drivers installed - suddenly no audio device.

[GeV]

I use the internal sound off my motherboard (worked fine), a USB sound adapter (worked fine), and
I'm recently playing with a firewire sound adapter. Suddenly today nothing is working. In Control
Panel, Sound, both Volume and Audio tells me "No Audio Device". I go into Hardware and all 3 audio
devices are installed. Something must have blocked them. Anybody have any ideas? There seems to
be no way to select any of them to work. Under Audio, in the Default device its all greyed out.
Same with Sound recording. I used to use the USB adapter for the mic. So much for that.

[GeV]

>I use the internal sound off my motherboard (worked fine), a USB sound adapter (worked fine), and
>I'm recently playing with a firewire sound adapter. Suddenly today nothing is working. In
>Control Panel, Sound, both Volume and Audio tells me "No Audio Device". I go into Hardware and all
>3 audio devices are installed. Something must have blocked them. Anybody have any ideas? There
>seems to be no way to select any of them to work. Under Audio, in the Default device its all
>greyed out. Same with Sound recording. I used to use the USB adapter for the mic. So much for
>that.

So I restarted the computer after uninstalling the firewire adapter and all is well. All devices
show up. I'd still love to hear from someone who might know why all audio devices were suddenly
unavailable. I do notice that all of a sudden the Windows Security Center icon is in the systray
though the setting seem to be the same as before. Firewall and Virus Protection is On and Automatic
Updates are off. I just started using the AVG firewall. I wonder if this could have caused this?