SORTED (by reading the bloody manual)! Audient Sono help please.

Evan

I’ve just bought an Audient Sono interface and before I go sending it back to Andertons, I’d appreciate it if some kind Sono owner would tell me if I’m missing something here. 

The issue is, when I plug a guitar lead into the guitar input on the front and press the “to valve” button on the back, the little green LED doesn’t light up, but if I pull the guitar lead out or even half way out, it lights up. It also lights up when a microphone is plugged into the back.

I’ve sent a message to Audient asking for help, but I probably won’t hear back from them for a few days, so if anybody can help before then, my thanks in advance.