>>95
これでどう？

-(IBAction)play:(id)sender{
NSSound *aSound=[NSSound soundNamed:@"sound.aiff"];

[aSound setDelegate:self];

repeat=YES;
[aSound play];
}

-(IBAction)stop:(id)sender{
repeat=NO;
}

-(void)sound:(NSSound *)sound didFinishPlaying:(BOOL)aBool{
if (repeat) [sound play];
}