What happens if you do this in the makefile: ldlibs = -l:libfluidsynth.2.3.5.dylib -Wl,-R.
What happens if you do this in the makefile:
ldlibs = -l:libfluidsynth.2.3.5.dylib -Wl,-R.
-lc -l:libfluidsynth.2.3.5.dylib -Wl,-R
ld: library not found for -l:libfluidsynth.2.3.5.dylib