Originally Posted by JimN
Do you ever use shorting plugs at the amp(s)? I have some from when I sold home audio- Sony supplied them for the unused phono jacks on integrated amps/preamps that had two phon inputs, to decrease noise pickup. I used them as an additional test if I found noise on shorted cables, just to verify/eliminate the cables as the source.
No, not normally. The input selector would normally take unused RCA inputs out of the circuit. But I guess the two phono inputs were not on a selector and internally paralleled. It makes great sense.
But we do use a shorting RCA jumper at the input of the amplifier to isolate, test and eliminate the amplifier as a source of noise. Then we move the jumper to the opposite end of the long RCA to eliminate the cable.