Potential wall socket fault
get a cheep volt meter and see if ground to neutral is 0 ground to hot is 115-120 and if hot to neutral is 115-120 if ground does not match neutral or there is voltage between ground and neutral there is a problem. I have a outlet that gets 50v between neutral and ground but the other 2 are normal. the electrician who put that in there some how managed to also flip the hot and neutral in the walls so that both breaker side and wall side look like they are wired properly but are reversed.  a cheep volt meter is 15-40$.  the battery units are pretty decent at telling you there is some kind of problem but not what it is.  duno about surge bars though.