John wrote:

Mine had springy contacts in each lampholder to make contact with the
conducting bars. Dust and cheap manufacturing had caused poor contacts in
each holder. A strip and clean sorted it.


Ah, that's a point. I can get the entire track down, not sure how far
the individual units will strip, but I'll have a look at that tomorrow.

Harry, I'd get nowhere taking them back to the supplier - no longer
proof of purchase, and I doubt they make the same units any more (twas
one of the sheds).

My family are heavily biased in the electronics/electric skills, so
there's a possibility of fixing if it's the transformer that has a fault
- I'm just interested in working out what it is as well as I can before
I start asking for a visit from them :-) If it's something simple that
I can fix then it's less hassle all around, really!

Velvet