We need to think of something so LOUD that it drowns out the 5 daily calls to prayer.
Maybe a carnival?
Now, what is we could take the taped call to arms (prayer?), and re-record it 1/2 phase out of sync, playing it at the same volume as the muslim arms depot next door.
Hopefully it would cancel out or so muddy the noise as to make it useless.
http://www.sweetwater.com/expert-center/glossary/t—PhaseCancellation