But I had problems making it play in 5.1 on my Theta Compli Blu (= Oppo), on which it defaulted to stereo. There are no helpful instructions and I was getting ready to return it as faulty. One more go revealed that a complex and unintuitive sequence will get you there, as long as you are patient: 1. press 'Play', wait for a yellow drop-down menu; 2. arrow down to 'Set up Audio'; 3. press Enter; 4. arrow right; 5. arrow up to 'Play Main Feature'; 6 press 'Enter' and wait - you can't skip the warm up and Conductors entrance. Then you should enjoy wonderful sound!
A pity that the end of the Planets segues directly into the Talbot final, which you may well not want to hear immediately the wonderful womens' voices fade.