Along the SB16 LLE improvements I've bothered to check why MSCDEX DOS redbook didn't work.
Say hello to
sjgplay, which is an open source audio CD DOS player.
Fixing this problem also means fixing hiccups/no redbook in games that uses it (zyclunt).
It's "working" as far as base playback goes, it has issues like with pausing or using the intro feature, to not mention that is supposed to read Karaoke CD+G format too ...