Audio player works in dev mode, but not in private beta

I have an app that is playing tracks from an RSS feed.

When I upload the development zip file to my roku, the tracks play fine.

when I uploaded the package to a private beta channel, the app loads, lists the tracks and shows a playing status, but there is no audio coming from the device.

I thought perhaps it was my audio settings (connected via hdmi) but I tried pandora and heard audio just fine, so the speakers work, the roku works, and the audio works.

but my app doesn’t work.

Before I spend any time hacking through my code, is there any specific reason why this would work on my dev roku but not my test live private beta installed roku?

many thanks
josh