Chromecast of DVR No Sound

I subscribe to the DVR Xfinity service and have recorded and use Chromecast to cast (via WiFi) recorded content to an Android TV.  Sometime over the last week, something broke.  I can no longer hear sound on the TV.  The sound comes through fine when I watch the recorded shows on my phone's Xfinity app.  And the sound comes through fine when I Chromecast Live TV from my phone's Xfinity app.  I get no sound when I Chromecast DVR content to my TV.  I have the volume level on my phone and TV turned up.  I can also cast from my MacBook Pro after logging into my Xfinity account and browsing to https://www.xfinity.com/stream/recordings.  I get no audio when Chromecasting DVR content to the TV using this method as well.