Tempest 'flyby' sound issue since 3.201b

[GSHWK_Houndstone_Hawk]

Thought I'd post here as a quick scan of the forum, I can't find a topic on this and so apologise if there is.

 

As the title suggests, I'm noticing some very weird digitised 'droning' sounds from the Tempest whenever you view it either fly overhead or view it in flyby. The engine noise is slowly replaced by this very strange 'droning' noise when the aircraft is overhead and flying away from your view/hearing spot.

Mods on or off, makes no difference (and since 3.201, not been running any mods).