selectAudioTrack() can break playback

[xxoo]

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?
the nightly version

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?
both

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

What browser and OS are you using?
Chrome, Firefox and Safari on macOS 15

For embedded devices (smart TVs, etc.), what model and firmware version are you using?
N/A

What are the manifest and license server URIs?
https://devstreaming-cdn.apple.com/videos/streaming/examples/bipbop_16x9/bipbop_16x9_variant.m3u8

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

{
	"manifest": {
		"dash": {
			"clockSyncUri": "https://time.akamai.com/?ms&iso"
		}
	},
	"preferredAudioLanguage": "en-US",
	"preferredTextLanguage": "en-US"
}

What did you do?
Open the video in demo. Then run:

shakaDemoMain.player_.selectAudioTrack(shakaDemoMain.player_.getAudioTracks()[1]);

wait for a few seconds

shakaDemoMain.player_.selectAudioTrack(shakaDemoMain.player_.getAudioTracks()[0]);

What did you expect to happen?
The video should still be playable.

What actually happened?
The video is stuck forever.

Are you planning to send a PR to fix it?
no

[avelad]

See #8738 (comment)

[xxoo]

@avelad
Thanks again! The problem seems solved on Chrome. But not on Safari and Firefox. In my test it even get worse on Safari. The video is stuck after switching audio for the first time. On Firefox the result is still the same as before.

[avelad]

In my case it is working correctly in Firefox, but it fails in Safari :(

8737.mp4

[xxoo]

This is my test on Firefox:
https://github.com/user-attachments/assets/4a3e09d4-2eb9-41c4-945e-b72b7c0f539f
On Safari:
https://github.com/user-attachments/assets/a3ed6502-814b-4937-851b-775f17d046be
Please let me know if you need more information

[avelad]

I've seen several things that could be improved. Every time we change the audio, we reset MSE when it's not necessary. ChangeType can be used, and it's much better from a user perspective. Safari doesn't support switching from audio/mp4 to audio/aac when using sequenceMode, so in some cases, we should transmux to avoid having to reset.

I'll have the changes ready in PR later today.