I've had my Audi A6 (W reg) for approx 2years. Not once has it given a problem until recently. For the last few months the headlights keep blowing individually. I have had them replaced and made sure the mechanic is putting them in correctly. He has pointed out you can't put them in any other way. The bulbs being used are Bosch premium bulbs.

Can someone please advise as it is really killing me knowing there is a fault with my car. HELP!!

Thanks