If your arm mesh and your torso mesh are different pieces you could establish their collision priorities as one and two, otherwise, the cloth really has a hard time deciding where it should be, you could try making a mesh constraint on the vertices that are sucking in for a few frames, then test it again a little later in the anim and see if you can sim with the constraint off. You can sim with the constraint off, if it sucks in, go back one frame truncate cache, turn the constraint on, re-sim. Down side is unrealistic movement, but if you're only doing it for a few frames it shouldn't be noticable.