This so-called "Advanced" linux audio is so completely broken. It should be so much simpler to compile this for FreeBSD, which has a working sound system.

It's asking a lot for Modartt (a small developer) to support FreeBSD, which is simply a very small user base with a lot "went our own way" about it.  It's generally not at all trivial to switch from one audio system to a completely different one.  It would require additional work in QA/testing as well.

It's quite possible that the libraries used by Modartt for cross platform development are not available on FreeBSD, in which case compiling it would be impossible even if Modartt has the resources to spare.

Moan as much as you like about ALSA (and who doesn't ?) but it has at least got support.  Whatever merits FreeBSD may or may not have (which is a debate for another time and place), Linux mainstream at least has a sound system that developers are willing to give limited support to.  FreeBSD is something like the 22nd most popular Linux distribution, but it has locked itself out of mainstream support (due to licensing) and it's not likely that the rest of the world will support it - it's hard enough to get Linux support (and thanks to Modartt for that !).

I doubt it's much help, but you might get Pianoteq running under Wine on FreeBSD or as a VM running another mainstream Linux distro, if you particularly want to do that.

You might be better asking on FreeBSD forums about ALSA and Jack2 support and workarounds.  I'd be surprised if someone hasn't tried addressing this in at least an unofficial port.

https://forum.manjaro.org/t/solved-alsa...vice/54450

It may be that Jack requires an update?

Happy hunting!

ALSA lib seq_hw.c:466:(snd_seq_hw_open) open /dev/snd/seq failed: No such file or directory
Pianoteq 6 STAGE: seq.c:1153: snd_seq_nonblock: Assertion `seq' failed.
Abort trap