Is FairPlay multi key encryption supposed to work in Safari 26 on macOS? It stopped working for us some time last year. The very same content works on iOS in AVPlayer and single key encryption works fine. On macOS, the multi key content sometimes plays, sometimes not. It is as if there was some race condition on how fast the KSM responds with content keys. Very often, I can see just one KSM request in network console (instead of multiple for each video profile and audio) and the playback fails with Video error: code=3 msg=Media failed to decode.
We've filed a Code Level Support ticket (19025185) and a bug report (FB22353469), but haven't really heard back. Just that engineering is actively investigating this issue, and was able to reproduce it.
