If you have no meter, unplug everything on the rack or flip your breaker. See if the tingling stops.
Stray current through my audio rack???
I don't know if I am imagining this, but each time I happened to touch my arm or put my finger into the grooves of the theaded metal rods of my Michael Green Audio rack, it feels "live", I kinda get a tingling....is there a way to check if there is some AC going through it?