I think I know what the problem is but I'm hoping I'm wrong. Occasionally my UFX (which is my primary interface in an aggregate setup) would seem to go off the rails and emit white noise through the AES/SPDIF out (I have my monitors digitally connected).

As of yesterday I can't seem to get the signal lights on the 4 mic preamps to stop being lit up and the device is suggesting that it is receiving a signal through the mic preams though it isn't. Occasionally turning it on and off or unplugging and plugging in firewire, usb, disconnecting adat etc seems to help for a bit but then it's back.

I'm suspecting some capacitors have gone bad internally and it needs to go in for service.

Does this issue ring a bell for anyone?