AudioServicesPlaySystemSound Won't Play Sound

Question

I have the following code to play some brief audio, and while it plays on the iOS Simulator, it won't play on a real device.

NSString *fileName = @"some_file_name";

SystemSoundID alertSound;
NSURL *fileURL = [[NSBundle mainBundle] URLForResource:fileName
                                         withExtension:@"wav"];

AudioServicesCreateSystemSoundID((__bridge CFURLRef)fileURL, &alertSound);

AudioServicesPlaySystemSound(alertSound);

Answer 1

It turns out, someone else in my code base was setting

[[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryRecord].

This was causing my audio to be muted. I fixed this by changing AVAudioSessionCategoryRecord to AVAudioSessionCategoryPlayAndRecord.