My Fireface UC has all of a sudden started producing noise on my first two inputs, even when there's nothing connected to it. In my mixer it looks like this: http://i.imgur.com/d8UiNCl.png and the two SIG(nal) lights next to the input on the device itself are lit.

The device is just sitting on my desktop, there's not much that could've happened to it physically, does anybody have a clue about what this is?