Have you read the FAQ and checked for duplicate open issues?
Yes

If the problem is related to FairPlay, have you read the tutorial?

No

What version of Shaka Player are you using?

4.15

Can you reproduce the issue with our latest release version?
Yes

Can you reproduce the issue with the latest code from main?
Yes

Are you using the demo app or your own custom app?
custom

If custom app, can you reproduce the issue using our demo app?
yes

What browser and OS are you using?
Chrome 90 on Sony Bravia Youview

For embedded devices (smart TVs, etc.), what model and firmware version are you using?
Sony Bravia Bluefin Gen 6

What are the manifest and license server URIs?

I can provide via email if necessary, but it can be reproduced with any sample Playready drm asset.

What configuration are you using? What is the output of player.getNonDefaultConfiguration()?

default config with drm

What did you do?

I load a custom app with Shaka player setup to play an MPD asset with Playready DRM onto a Sony TV (Bluefin Gen6, EME version).

What did you expect to happen?
I expect playback to start and continue playing without any issues.

What actually happened?

Most of the time playback fails to start with fatal RESTRICTIONS CANNOT BE MET / 4012 error. When you keep reloading the app, occasionally it is able to start playback but usable variants list appears to be incorrect.

Are you planning to send a PR to fix it?
Yes. I submitted a PR to address this issue for a different Sony TV model in pull/8577. Now this issue is discovered in yet another Sony TV model called Bluefin that I was not aware of previously. I will just have to adjust userAgent detection in isSonyTV() in platform utility, so both models are captured.