I have my P12 setup with a turntable (Marantz TT-15S1) on a dedicated outlet so that I can use the power switching function of the PP instead of the awkward motor power switch at the rear of the turntable, which I just leave “on”.
When I switch that outlet on/off on the PP, it triggers my Mytek Manhattan II DAC (which has a phono pre-amp) as if the source selection button were pressed on its remote…weird!!! The Mytek is plugged into a completely different outlet on the PP and there seems to be no other electrical reason for the causality here.
Does the PP have an IR blaster function that fires when an outlet is switched? That is the only reason I can come up for this behavior.