Basket Interference

[benbret]

NFHS Boys Varsity. A1 has the ball in the low post. A1 spins and attempts about a 2 foot shot. B1 comes down the lane and goes up for the block. B1 is late in his block attempt and strikes the backboard very hard as the ball bounces off of the backboard and hits the front of the rim. The striking the backboard makes the rim vibrate and causes the ball to bounce out of the cylinder. B1 was making a legitimate play on the ball and R1 believes A1 would have scored if B1 had not slapped the backboard and caused the ball to come out of the cylinder. Has any rule been violated? Rule number