Flickering headlights 9-5 04

Hello!

I have a 9-5 04 with xenon headlights. I have a recurring problem with
the xenon headlights. After a while they start flickering and
eventually they turn themselves off.

I (or more precicly my dealer) have tried to change the bulbs. They
are very expenisive and it does not solve the problem.

Have anyone here experienced something similiar and how does one fix
it?

Thankful for all help.

Kristian VD