Subtitles persist when switching to another content

[defagos]

When switching between a content displaying subtitles (e.g. via automatic selection) to another one without subtitles, subtitles persist on the second content and never update anymore.

Issue type

Incorrect behavior

Environment information

• Library version: 7.1.0
• iOS / tvOS version: 16
• Device: Device or simulator

Reproducibility

Always reproducible

Steps to reproduce

1. Tweak the advanced demo player so that the skip forward button plays the Apple basic stream URL (which has no subtitles).
2. Play the Apple advanced stream with the demo and select an option that displays subtitle.
3. Tap on the skip button to switch to the basic stream. Subtitles incorrectly persist on screen

Remark: When doing the same with Pillarbox player using a playlist, the issue does not appear.