DLNA Casting to Lumin U2

Recently purchased the app for my iDevices.  Looking forward to an alternative to JRemote.  The app, in general, looks great. 

I am having an issue.  I can not cast to my Lumin U2.  The device shows up fine but does not stream music.  I can control the volume of the Lumin U2 so I know it is connecting.  Below is a bullet point summary of information:

• Can't stream music to my Lumin U2
• The Lumin U2 is recognized and connected at some level since I can control the volume of the Lumin U2.
• I can stream music directly to my iPhone and/or IPad
• I select the Lumin U2 by using the cast button after selecting play.
• The Lumin U2 is an extremely reliable device on my network.  I use JRiver/Jremote, MO 4 Media, Lumin DLNA app, and Roon with near 100% reliability.
• The Lumin U2 is connected, via USB, to a Mola Mola Tambaqui DAC
• I assume I am casting to the U2 via DLNA and not Apple AirPlay.  I have AirPlay disabled on the U2.  The U2 shows up clearly as a device in Media Center under Playing Now.

Obviously, the main issue to be able to stream music to the U2.  It is how I will use Whiskey River 99.5% of the time.  One last comment, I would prefer a more obvious/permanent way to select the U2 as the device to play to.

Thanks for this app (think we're going to need it as a replacement for JRemote)!!!