Hi there, i got the same problem as yours. Airodump doesn't pick up anything. I search the web with no luck and even here no one answered you. Did you worked it out yourself by any chance? On top of what you noticed i found out that my usb alfa adapter doesn't pick up any networks anymore after i go out from cosole and check the networks with the manager. And yes even mine goes orange from green.
I tried it yesterday with a live cd and worked perfectly, but not in virtual box.