Voltage Issue: Minor mV reading OK for "OV?"

[rsmiii]

Greetings; help appreciated.
Basic Single Ended Experimenter's Kit 3.0

All resistances and voltages check out, except:
Terminal 4: Spec OV – My reading is about 32mV
Terminal 18: Spec 0V – My reading is about 42mV

Troubling or good enough?

Possible consequence, or different issue: Right Red input yields great sound; but Left Black input yields very faint sound.

Help appreciated as always.

[Paul Birkeland]

0.032V and 0.042V are plenty close to 0V in an amplifier where there's 380V of B+.

The lack of sound is a different issue.  That could be a great, great many things, and you'd definitely want to double check the voltages on that side to be sure they are good.  If they are, look for solder that is shorting the center pin to shell of the left RCA jack or a wiring error in the left output transformer.