piket_client: Remove use of `simpleaudio`

piket_client/gui.py

     QWidget,
 )
 from PySide2.QtGui import QIcon
-from PySide2.QtCore import QObject, QSize, Qt, Signal, Slot
+from PySide2.QtMultimedia import QSoundEffect
+from PySide2.QtCore import QObject, QSize, Qt, Signal, Slot, QUrl
 
 # pylint: enable=E0611
 
 except ImportError:
     dbus = None
 
-from piket_client.sound import PLOP_WAVE, UNDO_WAVE
 from piket_client.model import (
     Person,
     ConsumptionType,
 
 LOG = logging.getLogger(__name__)
 
-
-def plop() -> None:
-    """ Asynchronously play the plop sound. """
-    PLOP_WAVE.play()
+PLOP_WAVE = QSoundEffect()
+UNDO_WAVE = QSoundEffect()
 
 
 class NameButton(QPushButton):
         LOG.debug("Button clicked.")
         result = self.person.add_consumption(self.active_id)
         if result:
-            plop()
+            PLOP_WAVE.play()
             self.setText(self.current_label)
             self.consumption_created.emit(result)
         else:
     # Set dark theme
     app.setStyleSheet(qdarkstyle.load_stylesheet_pyside2())
 
+    # Load sounds
+    global PLOP_WAVE, UNDO_WAVE
+    sounds_dir = os.path.join(os.path.dirname(__file__), "sounds")
+    PLOP_WAVE.setSource(QUrl.fromLocalFile(os.path.join(sounds_dir, "plop.wav")))
+    UNDO_WAVE.setSource(QUrl.fromLocalFile(os.path.join(sounds_dir, "undo.wav")))
+
     # Enlarge font size
     font = app.font()
     size = font.pointSize()

piket_client/sound.py

-"""
-Provides functions related to playing sounds.
-"""
-
-import os
-
-import simpleaudio as sa
-
-
-SOUNDS_DIR = os.path.join(os.path.dirname(__file__), "sounds")
-""" Contains the absolute path to the sounds directory. """
-
-PLOP_WAVE = sa.WaveObject.from_wave_file(os.path.join(SOUNDS_DIR, "plop.wav"))
-""" SimpleAudio WaveObject containing the plop sound. """
-
-UNDO_WAVE = sa.WaveObject.from_wave_file(os.path.join(SOUNDS_DIR, "undo.wav"))
-""" SimpleAudio WaveObject containing the undo sound. """