On Raspi 2 B I didn't get your code running.
Collecting pygame
Using cached https://files.pythonhosted.org/packages/61/06/3c25051549c252cc6fde01c8aeae90b96831370884504fe428a623316def/pygame-1.9.3.tar.gz
Complete output from command python setup.py egg_info:
WARNING, No "Setup" File Exists, Running "config.py"
Using UNIX configuration...
Hunting dependencies...
SDL : found 1.2.15
FONT : not found
IMAGE : not found
MIXER : not found
PNG : found
JPEG : not found
SCRAP : found
PORTMIDI: not found
PORTTIME: not found
FREETYPE: found 2.6.3
Missing dependencies
----------------------------------------
Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-build-5U0TdV/pygame/
sudo apt install python-pygame
python /home/pi/Soundboard/soundbox.py
Traceback (most recent call last):
File "/home/pi/.local/lib/python2.7/site-packages/pad4pi/rpi_gpio.py", line 111, in _onKeyPress
handler(keyPressed)
File "/home/pi/Soundboard/soundbox.py", line 49, in processKey
playSound(path)
File "/home/pi/Soundboard/soundbox.py", line 14, in playSound
mixer.music.load(path)
pygame.error: Unknown WAVE format
So I don't see how you got your code running.