Weird Channel Bug?

Well I tried this and that, and finally fixed that problem thoug I don't really understand why this works only this way. I got this method:

	Method PlayM( MusicNr:Byte )
	
		If ChannelPlaying( MusicChannel )
			StopChannel( MusicChannel );
		EndIf
		MusicChannel = AllocChannel( ); 'I added this line and that solved my problem
		MusicChannel = PlaySound( Music[MusicNr], MusicChannel );	
		
	EndMethod

I actually *dislike* code that works without absolutly understanding it. I mean I allocated the channel before, so why do I have to alloc again to prevent overwriting by my other channels. |confused| Anyway, nice to have it working.