PAL runs at 25fps on a 50mhz signal and NTSCU/J runs at 30fps on a 60mhz singnal when each is played on it's correct hardware will sound and look the same.
One is not slower that the other they both run at 1fps/2mhz unless they are played on the wrong hardware
Maybe they did redo some aspects of Azure Dreams, the PAL counter parts usually come out later sometimes over a year later and on ocation either have extra fixes or more in them, or maybe it is the emu as with alot of games they don't sound exactly the same through emulation, though it's not that easy to tell