Slow audio speed

[TornadoWarning]

I'm using Dolphin as a way to make working backups of my Wii discs and use said backups. For some reason, all of the sounds play at about half speed. They all play at the correct time, for example when opening a door the matching sound effect will play right away, but instead of being "Creak" it will be "Ccrreeaak". Does anyone know why this is happening and how to fix it?