I turned the table over and opened up the bottom. The mounting screws for the motor and the rest are all very snug. This is not when the motor is turned on, as when youre going to play a record. Rather when the table is plugged in and with the motor switch in the off postion!
Everything operates normally when playing a record. I flip the switch, the spindle turns the belt, which spins the platter. Fine.
The vibration is ever so slight and is easier to notice when the belt is off. I can feel it through the spindle, attached to the motors shaft. Like I said, ever so slight but its there. Maybe it is normal.Would you mind double checking yours with the belt off? Touch the spindle and let me know if it vibrates. This is not a "spinning" issue.
You say it sounds better with the bottom off. I'd like to try but what do you do with the wire which is fastened to the metal bottom? What other tweaks can you recommend?