Well the thing is, the only thing old SaltySD and post-v0.9 SaltySD have in common is
https://github.com/shinyquagsire23/SaltySD/blob/master/smash/sdsound.asm, and that's it. Basically there's only a few scenarios at this point which could cause things to go wrong in terms of SD file override:
- A file entry for a new file exists, but the file fails to load somehow
- An overridden file somehow gets loaded with the original file instead
- An alternate path of loading is executed which I'm not hooking, or am only partially hooking somehow (one instance of this existed before but it was fixed).
- sdmc somehow gets unmounted and causes one of the first two options
- Overridden file allocations are too big, or the modified file itself is bad
If the bug existed between original SaltySD and post-v0.9, simply due to the complete difference between the two (one hooks top-layer functions, the other hooks at the source of loading files and indexing) I'm more inclined to believe that the constant is an error in patching nus3banks, or a lack of patching some other file. I recall during early SaltySD testing I tested a param file for someone (I forget who) which added an additional BGM song to the menu random. So it wouldn't surprise me that perhaps there's param file edits which might need to be made for nus3banks. I also recall testing a Lucina voice mod (I think from the same person, again forgot who it was) which had the side effect of being completely mute if you tried to test it in the music/sfx test screen.