"Gareth Magennis" wrote in message ...

I mean, that SMPS PCB can't cost more than several dollars bought
in bulk, so the £300 plus must surely be a money making exercise
for repairing their own stuff that has broken because it is not good
enough not to break in the first place.

The cost to RCF of a switching power supply for a sound-reinforcement speaker
has to be considerably more than a couple of dollars.

That said... many companies feel that their service departments should be
profit centers (rather than just breaking even), and don't care whether the
customer is happy. From my warped, anti-capitalistic point of view, a business
is entitled to only one profit on a sale.