Issue Summary:
I am using the native Kepler Video Player for Movies and Series playback and Shaka Player for Live Streams.
I have observed that player controls (Play/Pause, Seek Forward, Seek Backward, Playback Speed, etc.) behave differently depending on the actual container format of the video.
Expected Behavior:
Player controls should work consistently regardless of whether the file extension is .mp4, provided the video is playable by the native Kepler player.
Observed Behavior:
Case 1 (Working):
File Extension: .mp4
Actual Container: MP4
Result:
Play/Pause works
Forward/Backward seek works
Playback controls work correctly
Case 2 (Not Working):
File Extension: .mp4
Actual Container: MKV
Result:
Video playback starts successfully
Player controls do not function correctly
Seek Forward/Backward does not work
Playback speed controls do not work
Other transport controls appear unavailable
Additional Information:
Native Kepler Player is used for Movies and Series.
Shaka Player is used only for Live Streams.
The issue occurs on physical Vega OS TV devices & simulator.
Questions:
Does the native Kepler player officially support MKV containers when the file extension is .mp4?
Are transport controls (seek, playback speed, pause/resume) only supported for specific container formats?
Is there a recommended way to detect unsupported container formats before playback?
Sample Media:
I can provide sample URLs demonstrating both working and non-working cases if required.
Regarding MKV support: The Vega Media Player officially supports MKV containers in URL mode (refer: Media Player docs) Supported URL mode formats are: MP4, MP3, MKV, FLV, OGG, FLAC.
However, your specific scenario - where the file extension is .mp4 but the actual container is MKV - is likely causing a format detection issue.
We are investigating internally to confirm:
Whether the player relies on the file extension or inspects file header bytes to determine the container format
Whether transport controls are expected to work in this mismatch scenario
If there’s a recommended workaround when you cannot control the URL extension
In the meantime, could you confirm:
Are you able to test the same content served with a .mkv extension to verify controls work correctly?
What Content-Type header does the server return for these URLs?
The video plays successfully when served with the .mkv extension.
However, transport controls still do not function correctly.
Seek Forward and Seek Backward are not working.
Playback Speed controls are not working.
Playback itself starts and plays normally without errors.
For comparison:
MP4 container + .mp4 extension → Video playback and transport controls work correctly.
MKV container + .mkv extension → Video playback works, but transport controls do not work.
Based on this testing, the issue does not appear to be caused only by the mismatch between the URL extension and the actual container format. The behavior suggests that transport controls may not be fully supported for MKV content in the Vega Media Player, even when the content is served with the correct .mkv extension.
Could you also clarify whether there is any recommended approach to enable transport controls for MKV content?
For example:
Is there a specific player configuration required?
Are seek and playback speed controls only supported for certain container formats?
Is transcoding/remuxing MKV content to MP4 currently the recommended workaround?
Are there any documented limitations for MKV playback regarding transport controls?
I would appreciate any guidance, as many content sources may provide MKV streams and I would like to ensure a consistent user experience.
Please let me know if you need additional sample URLs or test content.
MP4: playback, seeking, and playback speed controls work correctly.
MKV: playback works correctly, but seek forward, seek backward, and playback speed controls do not function.
Since the same behavior occurs with a third-party MKV sample, this does not appear to be related to our server configuration, URL format, or specific media files.
Based on the Vega documentation, MKV is listed as a supported URL-mode format. However, I have not found documentation clarifying whether transport controls (seeking and playback-rate changes) are expected to be fully supported for MKV content.
Could you please confirm whether:
MKV transport control support is expected on Vega devices?
This behavior is a known issue or limitation?
Remuxing/transcoding MKV to MP4 is currently the recommended workaround?
There are any documented restrictions regarding MKV seeking or playback-rate control?
At the moment this is blocking our implementation because a significant portion of content is provided as MKV.