If unplugging the PAW from the PowerDrive2 stops it, plug something else into the PowerDrive2 and see if it comes back (i.e. plug in a phone or iPad).
If it does, then the PowerDrive2 is the problem, if not then the PAW is the problem.
If it's the PAW, unplug the SDR (ADSB receiver) dongle and see if it stops then, the problem is then the SDR dongle.
Most of the time these issues are the power supply, then the SDR dongle.