Clean your room! Your code is much too chaotic for you to expect us to figure out on our own. Rather than you assuming you know what the problem is and only asking for us a small solution to get your chaotic code to work, maybe you should instead explain what you are trying to accomplish.

If you truly do believe that the problem is where you think it is, then raise an exception when the values for $mon and $name are undefined or not what you expect them to be. And don't forget next time to Clean your room. :) Don't just give us the whole script, rewrite just the portion you are having trouble with -- by doing so you might just solve the problem yourself.

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)