Strange propeller speed change when using VOX

[Rebel28]

When using VOX the propeller momentarily changes speed every time you either transmit or receive voice. The sound of the engine does not change but visually you can see a change in the rpm of the prop. 

[1stpar3]

I have noticed this recently as well...but I am VR, so wrote it off as a VR thing. I DO NOT notice the change on instruments, its a flux when looking through gunsight and notice a wave or shimmer of prop. This also happens FOR ME,in VR, when flying some planes(mainly the F-4u). I also sometimes get a minimization to desk top upon releasing transmit button(like in big radio use moments). Doesnt happen but maybe twice a night.

[hitech]

This sounds like a lot like a strobe effect that could happen with a slight change in FPS. Which could be happening when you key the mic.

HiTech