[nigelr2000]

it's not a simple as a switch feeding a motor, if it's the same as its big brothers it will be microprocessor control where nothing will happen unless it is in the right status to start with so check for iffy skeleton microswitches that the larger VZ's suffer from also try moving the arm motor by hand so it is part way into a record with no power then plug it in and see if it resets to rest, this will show if everything else is working. I didn't see many of these and am more familiar with the upright range so can't really be much more help apart from thinking that 30 volts is way to high, I would expect 5 ish on the buttons and 12 on the motors. Also it is not unknown for the push button tact switches to fail so you could just try and force it into play by shorting the switch momentarily with a wire.