grundig guvp4200 plasma

[maff99]

Hi Guy's,I haveone of the above set's which had a faulty sub 5volt power supply.I replaced p.s.u. with a new one.set worked well for two weeks now it's come back to haunt me.This time when you switch on for about half a second you get a green on light then set reverts to stand-by.the new sub power supply
seems to be running o.k.If you switch the small service switch on the main power supply all the voltages seem to be correct.My gut feeling is that there is a problem on the main signal p.c.b. may be damaged by the first 5volt power supply failing.I noticed that C.H.S.sell one over £200 under the heading people who bought the sub p.s.u.also bought this item.Has anybody else come across this problem or anybody know what it is that may be causing this problem.any idea's guy's.I had one of these set's before with same p.s.u. fault.When i changed the p.s.u. & switched on the signal p.c.b. went up in smokeabout 5mins after switching it on.
many thank's Maff.