Azalea leaf spots
Sorry, I can't tell from the photo what's going on. Two suggestions: 1) contact your Montgomery Co. Extension office (below) and arrange to take a sample into them for diagnosis. (we'd be happy to do that here as well, but I'm guessing that MontCo office is closer for you.)
1015 Bridge Road, Suite H
Collegeville, PA 19426-1179 610-489-4315 MontgomeryExt@psu.edu
2) Check out this factsheet, and see if you can match symptoms with the problems described.