I have exactly the same problem and found no solution
what I analyse is a problem of loss of performance of one component joined with temperature (roughly, when it gets hot, it shuts off.... more and more early when gets older)
I found no solution
I am very dissapointed because H&B is no more imported in france (they gave up)... so nobody want to repair... if you find solution it would be great!!
ROUSSEAU Bernard, October 2007