headlight holder

[curtis2007]

i have a vw passat 1.9tdi 51 plate, thought one of my bulbs had gone, the outer bulb h7 one, upon taking off the rubber cup off the back and removing the bulb holder i noticed the black plastic holder what the wires connect to and bulb sits into was melting bulbs seem to of heated up soon as they were turned on one started smoking, i took off the passenger side bulb holder to find that was exactly the same, anyone have any ideas why this is happening or is it a common prob, was thinking maybe a fuse with to high rating or maybe summat allike if anyone has had the same prob or ideas i would be grateful.