If you look carefully you'll relise religion is a factor, and not really a cause... Poverty and political oppresion are also other factors, and the media also plays a huge role...
I'm a Sunni (pronouned Soon-knee, not sun-ny), and the big difference between the bile /tora and the koran is that the koran is MEMORISED... a muslim who knows the whole koran off by heart is not a rare or unsual occurance... At difficult time you can turn to religion, and the koran gives very clear instructions, but how certain poeple choose to interpret them is a very different matter... Also you can turn to good ol' logic... I dont really want to go into religion as it's all far too oppionated... but there's still not as big a difference between Sunni and Shia as there is between catholic/ prodestant...
Oh yeah, Islam does not forbid music, and there is nothing to say this, It's just certain groups feel the "message" carried by this media is not suitable...
If you thought there were similarities between prodestants and Sunnis, have a look at the MASSIVE parralels between judiasim and islam... Hebrew and arabic are paractically sister langauges... I was really surprised...