Hello everyone. Sorry to be away for so long. The local experts removed the radio and CD player and that seems to have done the trick. I don't really get it, as I took the fuses out and still got the drain, but anyway, now we have to find out what's amiss in the radio. I see there's a guy on eBay offering a fix for radio draining battery problems on another SEAT model for £70 a pop. Maybe it's a SEAT weakness.
Anyway, thank you all for your interest, good ideas, patience and modesty (isn't it endearing and true that the people who know most are the most understated about it?!).
Thanks again, and this is me signing off on this
problem.
johnmac