Per-player BGM volume doesn't persist

[gamefreq0]

While playing in single player (haven't tested on a server thus far), the per-player BGM volume setting doesn't appear to persist. It seems to randomly reset to 100% volume after some period of time ingame (perhaps at the point at which it switches to a new song? Further testing needed). It is guaranteed to reset when exiting to the menu and loading back into the world, which immediately starts playing the first song at 100% volume, so there's at least one easily replicable scenario to test here.

Easiest test to replicate the behavior is to load into a single player world, set the volume to something like 1%, exit to the menu, and load back in, at which point the first song plays immediately, at 100% volume.

[gamefreq0]

Update: I just confirmed it does reset at track change, by setting it to a low but audible volume, and then when the song changed, the volume went back up. Going back to the setting and decreasing or increasing it from that low volume, to force it to update, once again reduces the volume to the new level

[gamefreq0]

skyblock_zero/mods/sbz_base/init.lua

Line 216 in 9f5eb11

if volume == 0 and player:get_meta():get_int 'has_set_volume' == 0 then volume = 1 end

I suspect that has_set_volume might not be getting set in single player, perhaps? This sets volume to 100% if the variable is 0, so it's at least a likely candidate.

[gamefreq0]

Putting in a debug print statement, I determined that both volume and has_set_volume are 0 in single player when it checks, even midgame

[gamefreq0]

Further update: it only doesn't get set if you use the player settings formspec to set the volume. Using the command, it works just fine. So the issue is in saving the value from the formspec for the player, beyond the currently playing instance of the song