Clarify what could cause session.keyStatuses to always be empty

[XBDRX]

I'm implementing EME playback on a range of Smart TVs which support the spec "Encrypted Media Extensions W3C Working Draft 31 March 2015". The TVs have native DASH support so I am not using MSE.

I'm using commonly available test streams which I don't believe are using DASH features unsupported by the TVs:

Working
https://demo.unified-streaming.com/video/tears-of-steel/tears-of-steel-dash-playready.ism/.mpd

Not Working
https://media.axprod.net/TestVectors/v6.1-MultiDRM/Manifest_1080p.mpd

• Playready MediaKeySystemAccess is supported and media keys are created
• 'encrypted' events are received ok
• the license request appears to be successful
• the license response is sent to keySession.update
• 'handlekeyStatusesChange' event is received but keyStatuses is always empty
• playback doesn't start, no errors are generated and no further video events are received

I've read through https://www.w3.org/TR/2015/WD-encrypted-media-20150331/ several times and it's not clear to me what can cause this to happen or what actions I should take. Can someone please clarify?

ps in case it's relevant, the video source and mimeType are set via a child element rather than directly on the

[joeyparrish]

The spec you linked to is a 5-year-old working draft with a giant warning on it saying it's outdated:

But even in the current spec, I can think of no reason you should ever get empty key statuses. My guess is that this would be a bug in the EME implementation of that smart TV, and I would recommend that you file a bug with the manufacturer.

Does this help?

[XBDRX]

Correct. That's the version of the EME spec implemented by LG WebOS 4.0 (2018) and WebOS 4.5 (2019) Smart TVs.

http://webostv.developer.lge.com/discover/specifications/supported-media-formats/

I will assume a bug in their implementation and discuss with them. I do notice that Shaka works on those devices so I will test those same streams using Shaka rather than my own EME-based implementation.