Mxsmanic wrote in
:

I note that the Baron (and presumably other twins) has a prop sync
switch that somehow synchronizes the prop speeds on both engines.
From recordings I've heard of the interior noise of the aircraft, it
does sound as though props that are just slightly out of sync can
produce a very irritating intermittent noise as they move in and out
of phase.

If you want to simulate that accurately, just talk while your's jerking off
with your sim

Berti e