Hi @jonas!
I just installed and tested version 1.0.3-13-g58eec8df and the error persists (I tested it using this .m3u8 streaming that VLC plays for me without problems).
However, although the problem of playing .m3u8 streams in SMP persists, in the end I managed to find an alternative link in RadioBrowser to listen to Radio 3 (with acc codec), which in this case does play it properly for me.
So for my part, the solution to the problem is no longer urgent, although it would be interesting if it were fixed for the needs of other people and possible future situations.
Please, let me know if you finally find a solution or if you want me to continue testing!
Thanks!