MC19 rethinks how an audio device is selected in Options.
Instead of leading with a somewhat cryptic mode like WASAPI or ASIO, the program now leads with the device name.
When you open the device list, a list of available devices on the system will be presented. The recommended output modes (ASIO and WASAPI) will be at the top, and less common modes will be nested in a submenu.
Device names are cleaned a little bit so they're easier to read. For example, MC18 might show 'Speakers (2- AudioQuest DragonFly)' but MC19 shows a more intuitive 'AudioQuest DragonFly'.
The default choide is 'Default Audio Device [Direct Sound]'. It will always be at the top of the list. If Windows can play sound, MC should be able to play sound when using this setting. Start here if you're having problems.
Here's a screenshot showing the change:
The dialog also makes it more obvious that you're configuring settings for a specific zone (and allows configuring multiple zones by changing the selection).
Read more about picking the best audio output mode for your device here:
http://wiki.jriver.com/index.php/Audio_Output_Modes