Stacking DC Blockers?

[sam_adams]

All of these devices report wiring as correct.

But it won't find the N-G swap condition or a bad N-G bond at the panel:

 

[GXAlan]

But it won't find the N-G swap condition or a bad N-G bond at the panel:
View attachment 288852

Won’t the GFCI tester/outlet address that?

 

[wwenze]

At this point I'd just pull an extension cord from a room that doesn't have this problem.

 

[sam_adams]

Won’t the GFCI tester/outlet address that?

If the OP was connected to a GFCI outlet or circuit with a GFCI outlet upstream the GFCI should trip with neutral-ground swap. The CMX-2 doesn't have a GFCI outlet in it.

 

[dedobot]

I bet there's potential between AVR's body and ground. You need electrician.

 

[Speedskater]

I would suspect a high or low AC line voltage problem. With a little "Kill-a-Watt" meter (or similar) check line voltage in several rooms. And again when hig powered appliances or HVAC are operating.

 

[DanielT]

At this point I'd just pull an extension cord from a room that doesn't have this problem.

Exactly, run a cord from an outlet in a room where it works to the bedroom. If it then works as it should, with all the stuff set up and plugged in as it is
(exactly the same with all connections of the devices, cables and so on, change nothing), compared with when it doesn't work with the stuff plugged into the bedroom sockets in the bedroom, then the fault can reasonably only lie in the sockets in the bedroom. Or?
This is something you can try right now. Probably the easiest way to troubleshoot.

If that is the case, I stand by what I said earlier: Talk to an electrician (if you do not have the necessary knowledge of electricity yourself).