I am experiencing this same issue on F14A,
On F14B it seems fine.
The way to trigger it in the F14A is
ECS Air source all normal, means when u spawn in air.
Then u decrease throttle to idle. You will hear the whine, i think from electronics. Fine.
Then u increase to Afterburner, electronics whine sound cuts off abruptly
Then u decrease to idle, the electronics whine comes back abruptly and loudly as well.
On the F14B, it seems the mixing is done better. The electronic whine sound is still cutting in when engine rpm goes low. BUT it is much much more subtle.
I think the distinction have to be made that i think the sound that cuts off is NOT the air source sound, but rather the general electronic/cockpit whine background sound?