I'm using the below code to input voice from iPhone and playing on speaker simultaneously. But I'm getting a lot of noise feedback sound. How can that be fixed?
import AVFoundation
// Setup engine and node instances
var engine = AVAudioEngine()
var delay = AVAudioUnitDelay()
var reverb = AVAudioUnitReverb()
var mixer = engine.mainMixerNode
var input = engine.inputNode
var output = engine.outputNode
var format = input.inputFormatForBus(0)
var error:NSError?
// Attach FX nodes to engine
engine.attachNode(delay)
engine.attachNode(reverb)
// Connect nodes
engine.connect(input, to: delay, format: format)
engine.connect(delay, to: reverb, format: format)
engine.connect(reverb, to: output, format: format)
// Start engine
engine.startAndReturnError(&error)