How can I release a sound using AVAudioPlayer?

I'm trying to create a "interactive interview" a soundboard with alot of buttons by using the AVFoundation framework. The soundboard is done but I have one problem, when I press one of my sounds it doesnt stop when I press a new one simultaneously. Is there a easy way of stopping the previous sound if a new one is pressed? My code looks like this

- (IBAction)playSound0 {
    NSString *path = [[NSBundle mainBundle] pathForResource:@"about" ofType:@"mp3"];
    AVAudioPlayer* theAudio = [[AVAudioPlayer alloc] initWithContentsOfURL:[NSURL fileURLWithPath:path] error:NULL];

    [theAudio play];
}

- (IBAction)playSound1 {
    NSString *path = [[NSBundle mainBundle] pathForResource:@"chillwhatup" ofType:@"mp3"];
   开发者_运维技巧 AVAudioPlayer* theAudio = [[AVAudioPlayer alloc] initWithContentsOfURL:[NSURL fileURLWithPath:path] error:NULL];

    [theAudio play];
}

- (IBAction)playSound2 {
    NSString *path = [[NSBundle mainBundle] pathForResource:@"gethighorgetlow" ofType:@"mp3"];
    AVAudioPlayer* theAudio = [[AVAudioPlayer alloc] initWithContentsOfURL:[NSURL fileURLWithPath:path] error:NULL];

    [theAudio play];
}

- (IBAction)playSound3 {
    NSString *path = [[NSBundle mainBundle] pathForResource:@"icamefromthere" ofType:@"mp3"];
    AVAudioPlayer* theAudio = [[AVAudioPlayer alloc] initWithContentsOfURL:[NSURL fileURLWithPath:path] error:NULL];

    [theAudio play];
}

- (IBAction)playSound4 {
    NSString *path = [[NSBundle mainBundle] pathForResource:@"idoeverythinggood" ofType:@"mp3"];
    AVAudioPlayer* theAudio = [[AVAudioPlayer alloc] initWithContentsOfURL:[NSURL fileURLWithPath:path] error:NULL];


    [theAudio play];

}

I would just have my class keep track of the sound last started and, before I started playing a new sound, stop the previous one, if it is still playing.

AVAudioPlayer has a stop method to stop the sound and a playing method to see if it is playing.