orkadian

My 2002 x5 3D comes with a strange sort of drone at around 1500 rpm or just over, seems to come from the engine compartment, it isn't the drive train as it is there when the car is stationary, rev it higher or lower and it does'nt seem to be there. I would nearly think an engine mount bracket was touching the chassis without any rubber if that makes any sense so wondering if anyone else has encountered such a thing?