AVAudioPlayer not playing iPad2 - objective-c

Question

New to IOS dev, I'm testing AVAudioplayer to play sound on iPad2 (Xcode 4.2 project, ARC/storyboard enabled). Sound plays ok in simulator and no error. No error on device either but no sound.
Been browsing this fine resource temple, but nothing I've tried based on feedback here has produced anything but deafening iPad silence. Could someone help? My .h:
#import <UIKit/UIKit.h>
#import <AVFoundation/AVFoundation.h>
#interface ViewController : UIViewController
<AVAudioPlayerDelegate>
{
AVAudioPlayer *audioPlayer;
UISlider *volumeControl;
UILabel *timerLabel;
NSTimer *playbackTimer;
}
#property (nonatomic, retain) IBOutlet UISlider *volumeControl;
#property (nonatomic, retain) IBOutlet UILabel *timerLabel;
#property (nonatomic, retain) NSTimer *playbackTimer;
#property (nonatomic, strong) AVAudioPlayer *audioPlayer;
-(IBAction) playAudio;
-(IBAction) stopAudio;
-(IBAction) adjustVolume;
#end
My .m:
#import "ViewController.h"
#implementation ViewController
#synthesize volumeControl, timerLabel, playbackTimer, audioPlayer;
-(void)playAudio
{
playbackTimer = [NSTimer scheduledTimerWithTimeInterval:1.0
target:self
selector:#selector(updateTime)
userInfo:nil
repeats:YES];
[audioPlayer play];
}
-(void)stopAudio
{
[playbackTimer invalidate];
[audioPlayer stop];
}
-(void)adjustVolume
{
if (audioPlayer != nil)
{
audioPlayer.volume = volumeControl.value;
}
}
-(void)updateTime
{
float minutes = floor(audioPlayer.currentTime/60);
float seconds = audioPlayer.currentTime - (minutes * 60);
float duration_minutes = floor(audioPlayer.duration/60);
float duration_seconds =
audioPlayer.duration - (duration_minutes * 60);
NSString *timeInfoString = [[NSString alloc]
initWithFormat:#"%0.0f.%0.0f / %0.0f.%0.0f",
minutes, seconds,
duration_minutes, duration_seconds];
timerLabel.text = timeInfoString;
}
-(void)audioPlayerDidFinishPlaying:
(AVAudioPlayer *)player successfully:(BOOL)flag
{
}
-(void)audioPlayerDecodeErrorDidOccur:
(AVAudioPlayer *)player error:(NSError *)error
{
}
-(void)audioPlayerBeginInterruption:(AVAudioPlayer *)player
{
}
-(void)audioPlayerEndInterruption:(AVAudioPlayer *)player
{
}
my viewDidLoad:
- (void)viewDidLoad {
[super viewDidLoad];
NSURL *url = [NSURL fileURLWithPath:[[NSBundle mainBundle]
pathForResource:#"song"
ofType:#"mp3"]];
NSError *error;
audioPlayer = [[AVAudioPlayer alloc]
initWithContentsOfURL:url
error:&error];
if (error)
{
NSLog(#"Error in audioPlayer: %#",
[error localizedDescription]);
} else {
audioPlayer.delegate = self;
[audioPlayer prepareToPlay];
}
[super viewDidLoad];
}

Answer 1

Make sure that the file is indeed an mp3 format. Make sure that you are copying the file into the bundle, and not playing off of local path on your desktop. Check the device volume. Check the return BOOL from the play call. all of these are possible explanations.

Answer 2

Is it not playing sounds at all? No sounds even with headphones plugged in? If it's just no sound through the built-in speaker, but sounds through headphones, make sure that your device ring/sounds volume isn't muted. Check the toggle switch on the side (if you have that set to mute vs orientation lock). The bell shouldn't be crossed out. Just because you press the volume up button doesn't mean it's unmuted from the speaker. Have you tested YouTube videos or music files to ensure your iPad isn't having hardware issues?