Check out these tabs. It's for the song From The Sky by Gojira.
The intro (0-0-0-0-0-0-3-3-3-3-3-3-2-2-2-2-2-2-2-2-2-2-2-2, etc) are down/up down/up strokes. And it's pretty fast(for a beginner like me). I've no problem with down strokes but my pick gets stuck behind the string almost every time on an up stroke. I am not having any trouble when I play it slowly, but it happens when I try to increase some speed.
What am I doing wrong? Not enough "loosening up"? Wrong angle? Please help!