I don’t think, see how, it could be 60Hz ground loop hum. The TT motor is powered by a plug in 120Vac two blade step down DC power supply. No equipment ground there.
The power supply’s 120V plug in 2 blades does not appear to be polarized, meaning the unit can be plugged in 180 degrees either way. You might try reversing it both directions.
Note the TT has a ground post lug on the back side of it. Did you run a ground wire from the ground post lug to the ground post lug on the Kanto YU6 speaker?
Are you using a pair of good shielded phono interconnect cables?
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