iPod integration and gas connection??

rhows

I have a 2009 impreza and every time I fill my gas tank, my iPod integration loses power and no longer works. I've mentioned this numerous times when I bring my car in for service and no one can find an answer. In fact, they tell me that it must be a coincidence- which i totally get- but without fail it happens every time!! Anyone have any insight?? It's not crucial, just annoying- especially on road trips.