Virtually no high beams on my 993?

[911Rob]

Just added a '96 993 TT to my stable; I love the car but have a challenge I can't seem to solve?

The car came with Bosch Xenon lights (low beam only) and H1? High beam bulbs. When I switch from lows to high the added H bulbs make little or no difference. I'd really like to have some decent high beams.

the H bulb in the high beam socket says 100W, but when they come on they barely add any brightness over the Xenon high voltage low beams.

Anyone got any suggestions to my challenge?

Thanks!
(Seems the older I get, the brighter I need my lights?)
Cheers,
(Reposted off 993 Board with no replies/ Searched everything on both boards and couldn't find any info; you're help is greatly appreciated, as always!!)