SDL audio issue with hivelytracker (porting attempt)

I've been trying to port the hivelytracker to FreeBSD. After a lot of
patching I was finally able to start it with:

SDL_AUDIODRIVER=disk

with dsp (default) I would always get:

Fragment size must be a power of two

when

SDL_OpenAudio(...)

was called.

I did some further digging and found some useful references in:

https://cgit.freebsd.org/ports/tree/audio/faudio/files/patch-src_FAudio__platform__sdl2.c

With this patch I was able to get the player to launch without the above
error:

https://github.com/ehaupt/ports-wip/blob/master/ports/audio/hivelytracker/files/patch-replay.c

The player now starts:

I can click on 'Load Mod', load a sample mod but as soon as I get 'Play
Song' I get:

Abort trap (core dumped)

I've been trying to get some sense by running it with truss but haven't
been very successful so far.

The work in progress port can be found here:
https://github.com/ehaupt/ports-wip/tree/master/ports/audio/hivelytracker

The port still needs some TLC (hardcoded paths, etc...). I'll fix that
before adding the port.

Could someone with SDL audio experience please have a look? I'd
appreciate the help.

Emanuel


[1] https://github.com/pete-gordon/hivelytracker