There have been several users who have reported that when starting a PMDG aircraft in P3D using the Cold and Dark start up that a sounds can be heard even with no ground equipment present. A user identified the possible sound of the source as the "fuel_pump.wav" file in the C:\Program Files (x86)\Lockheed Martin\Prepar3D v3\Sound folder. If you encounter this issue please try disabling this file and see if the problem is corrected for you.
Article ID: 120, Created: 6/28/2016 at 8:01 PM, Modified: 6/28/2016 at 8:01 PM