Using 2017.1.0b5 and am not sure whether its something I have missed.
I am using a Playable Director with Wrap Mode set to Loop and whilst the animations loop happily, the audio does not when I add an Audio Track, they play once and then stop.
Any pointers as to where I can look. I am using a script to manage the start and end of the timeline using playableDirector.Play() and had moved to the Timeline tool as it makes my workflow so much easier.