I think the trick is that, when you have configured the player the way you like it,then pressing 'Play' will load the disc and select the optimum quality soundtrack (in my case multichannel mlp) according to how your player is configured.If you alternatively press 'Close' to load the disc you will be expected to select from the Menu.
So if you have multichannel set to off then the next highest stereo track should be selected.

Regards,
Manus

Mostly harmless. Comfortably numb.