Motorhead hit in on the head, no pun intended.
There is a great chance that the thickness of the velcro is greater than the thickness of the calf skin.
A trick to helping arrows out that are too weak is to thicken your strike plate, moving your arrow farther away from center. I have done this quite a few times when getting a bow set up and don't have a heavier spined arrow on hand.
Use a thinner strike plate, or remove what is behind the strike plate, and your problem should be solved.