Sorry if this is the wrong place to post this. I have been getting very frustrated lately trying to figure this out. So I ditched the Audiobox USB I had because it started producing a loud noise when the phantom power was engaged for my Rode NT1, and bought a Focusrie Scarlett 2i2. I was having problems with self noise from the Presonus, not at first but a few times after recording with it. I thought buying a different pre would help, but the same noise is still there. I unplugged everything electrical that I didn't need, ran off of the Mac's battery, changed cables, tried all I could think of. My MBP is from 2007, don't know if that matters but it recognizes the Scarlett so I didn't think that was the issue. Other people record fine with itso iI am at a loss as to what the problem might be. Any helpwould be greatly aappreciated..