Running `buckle` using its path doesn't work—must `cd` into its directory

I'm getting the error discussed here: https://github.com/zevv/bucklespring/issues/21

Basically, if I `cd` into `/path/to/bucklespring` and run `./buckle`, it works perfectly.

But if I directly do `/path/to/bucklespring/buckle`, I get `Error opening audio file "./wav/32-1.wav": Failed to open file`.

macOS Sonoma, Fish shell