"Assertion Failed: Audio Device" upon trying to launch in Standalone

Trying to launch my game in standalone mode, but I’m getting this error:

Assertion failed: AudioDevice != nullptr [File:C:…UserSettings.cpp] [Line: 49]

I’ve tried plugging in headphones to the front and back of the machine. I already also have wireless headphones hooked up. This isn’t an issue with other projects, only this one.

Can anyone help me out?