Just a suggestion, and know it's probably figured out by now, but try going into your audio-options, I don't Ableton either, but you usually have to select what card you will be using. May come up Focusrite, may come up USB Audio interface, just make sure it's checked. And have you tried switching cables, where your XLRs go to monitors, and TRS to interface, might get better sound? Sorry if I didn't help, and way late, just found this great site, good luck!