That's a neat trick with the AM radio. I wonder if I still own one...

The wife reported that she usually heats her water up to 1.5 minutes
and that lately it seems to get alot hotter. This is at "high," that
is why I asked if there was cycling on high, then a no cycle condition
(stuck relay) would explain it. If there is normally no cycling on
high, which I guess is how these things are made, the only explanation
could be that the magnetron is putting out more energy than before, is
this possible? I have had problems in the past with blown fuses, but
replacing them gets the unit working again. Also, some mugs seem to
get real hot, which I am guessing translates in hotter water given the
same cook time.