Weird problem with stereo

Whenever I'm driving with the stereo turned on, if I come to a stop at traffic lights or traffic etc as soon as I stop moving foward, the stereo refuses to play.

No sound is omitted, yet as soon as I engage a gear and then drive fowards, the sound is back. The stereo stays turned on as the song has progressed but the sound was no where to be heard?

I assume this is a loose wire issue but why would it be caused by me stopping and moving? Sometimes it also does it when going over bumps but guaranteed every time I come to a standstill, the sound goes off...

Any ideas?

Low voltage at the stereo caused by bad connections maybe? Stupid auto volume control? An irritating ghost?

Where would the connections be?

Is there any wiring that could be loose by the pedals?