What could Account for This? RCA 9TC-240 Power Issue

[Chris K]

Fed the same tone into the pin 5 cathode of the 6AL5 (V118) discriminator and hear a very faint tone with full modulation gain on the generator that isn't changing with the TV volume control in fact, it's the easiest to hear with the volume control turned full down to minimum. It's very faint though I do hear it.