Xfinity Stream on Roku various issues

Have been seeing a lot of unstable behavior in the Xfinity Stream app on Roku. Have two Roku Premier+ (4630X) hardwired to the router (no wifi involved), feeding two different TVs,  on a Xfinity 1200 MB/s download service.

1. It takes sometimes 30 seconds for the Recent Channels icons to display when I start the app.

2. Over this past weekend, the Recent Channel display was oftentimes incomplete/not updated (doesn't show the channels I have just been viewing). Not seeing this issue today for whatever reason.

3. Video/audio freezing on several channels, requiring the app to be exited and re-started.

4. Video/audio unsynchronized, again requiring the app to be exited and restarted.

Been running this setup without major issues for over two years and just started to see these issues frequently over the last possibly 10 days or so. Both devices show that their firmware is up to date.

Any thoughts on root cause/ corrective actions? Is this app still in Beta?