What, me? (I'd sort of forgotten this entire thread, actually.)
No, it's in the dining room (which never actually gets used for dining anymore outside of maybe once a year if that); smoking is not permitted in the house, the dogs aren't allowed in, it's a gas fire. PC is (along with most everything else) on surge supressors because we are right next to the substation.)
As it happens, the card reader was still just in warrentee, so I contacted the seller on Amazon and they replaced it, so aside from being a nuisence, it didn't at least mean I had to replace it. (I mean, that to some extent says that they expect one to periodically go.)
(We had a bit of a bad week,tech-wise, that week.)