Microphone feedback noise and can I use the output to recognise?

I recently released my first ShazamKit app, but there is one thing that still bothers me.

When I started I followed the steps as documented by Apple right here : https://developer.apple.com/documentation/shazamkit/shsession/matching_audio_using_the_built-in_microphone

however when I was running this on iPad I receive a lot of high pitched feedback noise when I ran my app with this configuration. I got it to work by commenting out the output node and format and only use the input.

But now I want to be able to recognise the song that’s playing from the device that has my app open and was wondering if I need the output nodes for that or if I can do something else to prevent the Mic. Feedback from happening.

In short:

1. What can I do to prevent feedback from happening
2. Can I use the output of a device to recognise songs or do I just need to make sure that the microphone can run at the same time as playing music?

Other than that I really love the ShazamKit API and can highly recommend to have a go with it!

This is the code as documented in the above link (I just added the comments of what broke it for me)

func configureAudioEngine() {
    // Get the native audio format of the engine's input bus.
    let inputFormat = audioEngine.inputNode.inputFormat(forBus: 0)
    
    // THIS CREATES FEEDBACK ON IPAD PRO
    let outputFormat = AVAudioFormat(standardFormatWithSampleRate: 48000, channels: 1)
    
    // Create a mixer node to convert the input.
    audioEngine.attach(mixerNode)

    // Attach the mixer to the microphone input and the output of the audio engine.
    audioEngine.connect(audioEngine.inputNode, to: mixerNode, format: inputFormat)

    // THIS CREATES FEEDBACK ON IPAD PRO
    audioEngine.connect(mixerNode, to: audioEngine.outputNode, format: outputFormat)
        
    // Install a tap on the mixer node to capture the microphone audio.
    mixerNode.installTap(onBus: 0,
                         bufferSize: 8192,
                         format: outputFormat) { buffer, audioTime in
        // Add captured audio to the buffer used for making a match.
        self.addAudio(buffer: buffer, audioTime: audioTime)
    }
}