Thanks - it's a Bryton SP1.7.
I have not done any work to this yet because of waiting for them to supply any information, only visual inspection, I have not done any live testing .
However this is probably where I will start, as you and others say with experimenting with the resistor and capacitor values.
I can measure voltage, current, ripple and hum on the output and see what's going on.
It is possible there is a fault that is causing excessive current draw on one of the rails, so I'll check for that first.
I was intending to follow best practices when it comes to design of the supply, as it is obviously not complex, but obviously much better components are available now than when it was made so therefore it makes sense to think about what should be used instead of simply copying the original design. I am fairly sure that the ripple can be reduced to original figures without resorting to the same choice of filter resistances but obviously that's one for a little experimentation.
Thanks all