Aligns audio with video. 
		This should be called for instance after a seeking operation or resuming 
		from a pause.

def __calculate_audio_frames(self):
		""" Aligns audio with video. 
		This should be called for instance after a seeking operation or resuming 
		from a pause. """

		if self.audioformat is None:
			return
		start_frame = self.clock.current_frame
		totalsize = int(self.clip.audio.fps*self.clip.audio.duration)
		self.audio_times = list(range(0, totalsize, 
			self.audioformat['buffersize'])) + [totalsize]
		# Remove audio segments up to the starting frame
		del(self.audio_times[0:start_frame])