Alright, I was messing around with my MintyPi when I realized that the micro USB port on the right is specifically for power. If you plug the sound card into that one, it won't work. I didn't realize this because my micro USB converter would cover up the other micro USB port. Hope this helped.

I am having the same problem. I connected my sound card via USB, and not only has the problem persisted, but I'm not getting sound either. I'm using the newest MintyPi image. When I plug the sound card in, it just resets the raspberry pi.