Bugfixes and Improvements

• Fix stalling on discontinuity with audio track #2919 resolves #2913, #2545
• Fix initial audio video desync for fMP4 #2832
• Prevent immediate level switch from performing unnecessary pause and seeks #2918

Misc

• Functional test improvements #2921

This release is focused on stability in streams using alternate audio tracks. Live streams and streams with discontinuities frequently presented problems depending on the order in which playlists and media were received initially. With this release, regardless of that order, alt audio media will be synced to the variant playlist media, by deferring final parsing and appending of audio segments (not the fetching of) until they can be aligned with variant media PTS.