Hi guys, I have the Airnav Radarbox connected to a P.C. which is never switched off, therefor Airnav is permanently on, the signals are received from an outdoor antenna on the roof of the house, yesterday I lost all signals and no aircraft were displayed on screen, the power led is lit and the usb led is flashing, but no signal, all the connections seem to be ok..........what happened, or how can i troubleshoot to find the cause?