Random File Picker Picks Same Value On Each Execution (batch)

I'm trying to launch a random file with this software via a script - the only problem is that this script always selects the same random number on every launch. It's always 41 for me... Any suggestions?

@echo on
setlocal EnableDelayedExpansion
cd C:\Users\User\Documents\Downloads\Nintendo
set n=0
for %%f in (*.*) do (
  set /A n+=1
  set "file[!n!]=%%f"
)
set /A "rand=%random% * 100 / 32768+1"
"C:\Users\User\Downloads\fceux-2.2.2-win32\fceux.exe" "!file[%rand%]!"