HI-Z switch on UR22C

I’m a complete newcomer to using an audio interface with a computer so apologies if this seems a stupid question. I have just set up my new UR22C and have used it successfully with various mics. I have an electro acoustic guitar which I want to put through it. Do I need to press in the HI-Z button or is that only for electric guitar pick-ups? A related question is does it matter if I plug in the guitar cable before or after pressing the HI-Z button?
Any help will be much appreciated. Thanks.

Just test it without Hi-Z. If it doesn’t reproduce any sound or really quiet sound, enable Hi-Z. Make sure that the guitar is in input 2

Thankyou. It needs the HI-Z switch on.

Hi-Z is for passive instruments as Guitar/Bass with passive pickups.