Pro-Ject Phonobox MkII - no sound

This is probably a shot in the dark and/or a vague and unhelpful question but -

I recently got a Pro-Ject phono box to hook up a turntable to my focusrite soundcard and monitors, to listen to and record vinyl.

Bought it second hand (perhaps my first mistake) and it didnt come with a power supply. I tried an adapter I had that said it did a range (15-22v or something IIRC) and the phono box wants 16V so i thought it might work but it didnt. Bought a power supply new that is sold as being correct spec specifically for the preamp, still no signal coming through.

My question is whether i fried it with the first PSU or whether there are any other simple things i might be missing or components to poke inside with a multimeter that might diagnose the issue, dont want to chuck it but not exactly where to start with fixing it, aside from taking it to a repair person.

NB - when its all hooked up, theres a slight pop through the monitors when i plug in or unplug the sound, so there is something getting through, just not my music! 🙁

Any leads most welcome 🙂