iOS - Playback of recorded audio fails with OSStatus error -43 (file not found)

Question

I set up an AVAudioRecorder instance the following way when my view loads:

AVAudioSession *audioSession = [AVAudioSession sharedInstance];
audioSession.delegate = self;
[audioSession setActive:YES error:nil];
[audioSession setCategory:AVAudioSessionCategoryRecord error:nil];

NSString *tempDir = NSTemporaryDirectory();
NSString *soundFilePath = [tempDir stringByAppendingPathComponent:@"sound.m4a"];

NSURL *soundFileURL = [NSURL fileURLWithPath:soundFilePath];
NSLog(@"%@", soundFileURL);

NSDictionary *recordSettings = [NSDictionary dictionaryWithObjectsAndKeys:
                                [NSNumber numberWithInt:kAudioFormatMPEG4AAC], AVFormatIDKey,
                                [NSNumber numberWithInt:AVAudioQualityMin], AVEncoderAudioQualityKey,
                                [NSNumber numberWithInt:16], AVEncoderBitRateKey,
                                [NSNumber numberWithInt: 1], AVNumberOfChannelsKey,
                                [NSNumber numberWithFloat:8000.0], AVSampleRateKey,
                                [NSNumber numberWithInt:8], AVLinearPCMBitDepthKey,
                                nil];

NSError *error = nil;

self.recorder = [[AVAudioRecorder alloc]
                 initWithURL:soundFileURL
                 settings:recordSettings
                 error:&error];
self.recorder.delegate = self;

if (error) {
    NSLog(@"error: %@", [error localizedDescription]);
} else {
    [self.recorder prepareToRecord];
}

Then, when the user presses the record button I do:

- (IBAction)record:(id)sender {
    if (!self.isRecording) {
        self.isRecording = YES;
        [self.recorder record];
        self.recordButton.enabled = NO;
    }
}

Then to stop the recording/playback:

- (IBAction)stop:(id)sender {
    if (self.isRecording) {
        [self.recorder stop];
        self.recordButton.enabled = YES;
        self.isRecording = NO;
    }

    if (self.isPlaying) {
        [self.player stop];
        self.isPlaying = NO;
        self.playButton.enabled = YES;
    }
}

After, I want to be able to playback what was recorded, so I do the following:

- (IBAction)play:(id)sender {
    NSError *error = nil;
    self.player = [[AVAudioPlayer alloc] initWithContentsOfURL:self.recorder.url error:&error];
    self.player.delegate = self;

    if (error) {
        NSLog(@"%@", error.localizedDescription);
    } else {
        self.isPlaying = YES;
        [self.player play];
        self.playButton.enabled = NO;
    }
}

But when I go and play the file is get OSStatus error -43 file not found.

This is all running on the device btw, on the simulator y an error when trying to instantiate the recorder or player, and from I've seen it's a simulator issue.

EDIT 1: I solved the OSStatus error -43 part it has something to do with the encoding format, I commented out the format and it recorded and played the file properly, but I need to record in a compressed format. Does anyone know the settings for this?

EDIT 2: I managed to find settings that worked for compressed AAC audio. A 2min audio file comes out to 256KB, I updated my code to reflect the current state. Thanks to all of those who answered for your help.

Answer 1

I'm gonna take a wild stab at this since no-one else has answered (EDIT: now there is) (I don't have much experience with Audio in iOS) but...

Try changing

[[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryRecord error:nil];

to

[[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryPlayAndRecord error:nil];