I just got a scarlett 8i6 and cubase 6 the other day and I've been trying to set it up. I'm trying to use vst amp sims with my guitar plugged into the analog 3 input via a trs jack on the back of the interface. I can hear the instrument through scarlett mixcontrol, but when I got into cubase, it says that the line 3 input I'm using is inactive. So when I try to add a new audio track and select what I presume should be the line 3. The same thing happens when I try to plug into line 4. Does anyone know how to solve this? Sorry if this is simple or a stupid question. I'm new to cubase and interfaces.