I also see many people with same issue in this thread, however it’s a kind of mixed bag with many different issues:
I have the same problem on My TV Philips POS 9002 (Android TV) with the new player. Impossible to play any movies. No problem with the old player.
This is the plex client log
plexlognewplayer.txt (192.8 KB)
Thanks! While we investigate, can you please try 7.30, which was just released, and let me know how it goes? Same thing as well, if you could @uzuhu69? 
Just tested again on 7.30
Still doesn’t work. But hey - it was re-enabled automatically again, so it might be on every app update 
Which sucks when it doesn’t work.
Ok, maybe I just forgot that I left it on during my testing yesterday. But the important thing is that it still doesn’t work…
Yes it doesn’t work with latest version of plex with the new player. Same thing. Works with the old player.
If it’s still not working, can you please provide some logs and sample files, please? 
I already provided log. The log also shows that a sample file shouldn’t really be necessary, as the issue is something else. The issue is also well documented in the other thread I linked. I can even provide the steps for reproduction:
- Set up plex server
- Make sure new player is enabled in Plex app on Android TV device (should be, since it’s enabled by default).
- Try to play any media from said Android TV device on the same LAN network as the server.
- Media fails to play, and shows same error message as I photo’d above.
A log from 7.30, please. Plus, my reply wasn’t directed at you, but at @uzuhu69
New log from 7.30.0.16390
Exactly same error. Nothing changed. Any chance for ETA of fix? This affects anyone who uses an ATV client in the same household as server. The other thread said a fix is coming, but 3 months later there’s been no word on said fix.
plex error log.txt (60.7 KB)
I’ve not even looked at the new logs yet. We also don’t provide ETAs for changes. The same user facing error can actually have multiple different causes behind it, so it’s not a 1:1 ratio with error messages to actual issues.
No but in the other thread, I’ve analyzed their logs and confirmed it’s the same issue.
At the very least, I think this “new player” shouldn’t be enabled by default, until it’s somewhat stable.
Are there changelogs on new version of Android TV app?
EDIT: Found the changelog. However, it says the new player is now default enabled. I believe it’s been so for a longer while.
Interesting. Is it on the same LAN network as your server?
The Android TV device that plays fine with “new player” enabled. Is that device on the same local network as the plex server that it’s streaming from?
If it’s not too much trouble, I’d be interested in seeing the log when you start playback.
There’s another thread on the issue here: My Plex Server is failing to HW transcode when starting media from a Shield
With more technical information and a possible workaround. However, I can’t seem to implement that workaround, so I’m still facing the issue.
If you dig into the thread and the logs, you’ll see the issue is the same.
The titles of the threads indicate that the issues are different. But if you read the posts, it shows that the issue is the same. If you don’t have anything to contribute, please stop derailing this thread.
This appears to be related to DNS rebinding, which is fixed internally, and should be available in the upcoming v7.31 beta 
7.31 is now available in beta 