mustContainAudio

https://datatracker.ietf.org/doc/html/rfc6381:

When the 'codecs' parameter is used, it MUST contain all codecs indicated by the content present in the body part. The 'codecs' parameter MUST NOT include any codecs that are not indicated by any media elements in the body part.

This means that codecs cant be used "|| format.codecs?.split(",")?.any { MimeTypes.isAudio(MimeTypes.getMediaMimeType(it)) } == true" They may be used for harsher restriction on "audioGroupId == null", but codecs is optional

https://datatracker.ietf.org/doc/html/rfc8216

Since the EXT-X-STREAM-INF tag has no AUDIO attribute, all video Renditions would be required to contain the audio.

However it may still contain audio with the AUDIO attribute, therefore we also check the audio with that groupId:

If the media type is VIDEO or AUDIO, a missing URI attribute indicates that the media data for this Rendition is included in the Media Playlist of any EXT-X-STREAM-INF tag referencing this EXT- X-MEDIA tag.

But this is not foolproof, because TS segments needs to be investigated to be sure as I do not see any way to detect this from the m3u8 playlist