Ran across these issues when testing sounds. Loaded default sounds - same issues.
All external listening from another nearby Ground vehicle.
m3: 50 cal sound audible when fired.
m16 50 cal sounds audible when fired.
m8: 50 cal pintle gun or secondary MG NOT audible when fired.
LVTA2 - 50 cal audible when fired - not sure on 30cal.
LVTA4 - pintle gun NOT audible.
Panzer - pintle gun/turret MG / hull gun NOT audible
Tiger - Pintle / turret Mg/ hull gun NOT audible
OSTWIND - same issues as with manned 37mm aa...using "m2.wav" so main osty gun sounds like a m16 firing externally. No hull gun sounds
Also..Muzzle flashes from vehicles firing at you are not seen..least the small caliber guns.