I got a iRig Pro Dou I/O a few days ago to use as a simpler and more portable interface for audio recording into GarageBand on iOS. I was mainly interested in being able to have one active recording track and one dummy track without a mic so I can record in track view. But I’m getting a lot of background crackle on my test audio recordings. I have two different dynamic mics to try, but getting the same result. Only one XLR cable however. I’m getting the crackle in the monitor headphones as soon as the iRig I/O gets plugged into the lightning port before the record button is hit. I have the gain on the port not in use to 0, and tried various gain settings on the port in use. Not using the power adapter because I don’t have condenser mics, and the 48 v switch is off, but I still had the flashing upper left red light indicating low batteries, so I put in new batteries.
I wasn’t having this problem with my old and not class compliant audio interface.
Sounds like this: https://soundcloud.app.goo.gl/3L3kzH6zNke7SCVT6