Audiokit logging - 55: EXCEPTION (-1): "" - repeatedly - swift

Question

I updated to latest version of Audiokit 4.5
and my Audiokit class that is meant to listen to microphone amplitude is now printing: 55: EXCEPTION (-1): "" infinitely on the console. the app doesnt crash or anything.. but is logging that.
My app is a video camera app that records using GPUImage library.
The logs appear only when I start recording for some reason.
In addition to that. My onAmplitudeUpdate callback method no longer outputs anything, just 0.0 values. This didnt happen before updating Audiokit. Any ideas here ?
Here is my class:
// G8Audiokit.swift
// GenerateToolkit
//
// Created by Omar Juarez Ortiz on 2017-08-03.
// Copyright © 2017 All rights reserved.
//
import Foundation
import AudioKit
class G8Audiokit{
//Variables for Audio audioAnalysis
var microphone: AKMicrophone! // Device Microphone
var amplitudeTracker: AKAmplitudeTracker! // Tracks the amplitude of the microphone
var signalBooster: AKBooster! // boosts the signal
var audioAnalysisTimer: Timer? // Continuously calls audioAnalysis function
let amplitudeBuffSize = 10 // Smaller buffer will yield more amplitude responiveness and instability, higher value will respond slower but will be smoother
var amplitudeBuffer: [Double] // This stores a rolling window of amplitude values, used to get average amplitude
public var onAmplitudeUpdate: ((_ value: Float) -> ())?
static let sharedInstance = G8Audiokit()
private init(){ //private because that way the class can only be initialized by itself.
self.amplitudeBuffer = [Double](repeating: 0.0, count: amplitudeBuffSize)
startAudioAnalysis()
}
// public override init() {
// // Initialize the audio buffer with zeros
//
// }
/**
Set up AudioKit Processing Pipeline and start the audio analysis.
*/
func startAudioAnalysis(){
stopAudioAnalysis()
// Settings
AKSettings.bufferLength = .medium // Set's the audio signal buffer size
do {
try AKSettings.setSession(category: .playAndRecord)
} catch {
AKLog("Could not set session category.")
}
// ----------------
// Input + Pipeline
// Initialize the built-in Microphone
microphone = AKMicrophone()
// Pre-processing
signalBooster = AKBooster(microphone)
signalBooster.gain = 5.0 // When video recording starts, the signal gets boosted to the equivalent of 5.0, so we're setting it to 5.0 here and changing it to 1.0 when we start video recording.
// Filter out anything outside human voice range
let highPass = AKHighPassFilter(signalBooster, cutoffFrequency: 55) // Lowered this a bit to be more sensitive to bass-drums
let lowPass = AKLowPassFilter(highPass, cutoffFrequency: 255)
// At this point you don't have much signal left, so you balance it against the original signal!
let rebalanced = AKBalancer(lowPass, comparator: signalBooster)
// Track the amplitude of the rebalanced signal, we use this value for audio reactivity
amplitudeTracker = AKAmplitudeTracker(rebalanced)
// Mute the audio that gets routed to the device output, preventing feedback
let silence = AKBooster(amplitudeTracker, gain:0)
// We need to complete the chain, routing silenced audio to the output
AudioKit.output = silence
// Start the chain and timer callback
do{ try AudioKit.start(); }
catch{}
audioAnalysisTimer = Timer.scheduledTimer(timeInterval: 0.01,
target: self,
selector: #selector(audioAnalysis),
userInfo: nil,
repeats: true)
// Put the timer on the main thread so UI updates don't interrupt
RunLoop.main.add(audioAnalysisTimer!, forMode: RunLoopMode.commonModes)
}
// Call this when closing the app or going to background
public func stopAudioAnalysis(){
audioAnalysisTimer?.invalidate()
AudioKit.disconnectAllInputs() // Disconnect all AudioKit components, so they can be relinked when we call startAudioAnalysis()
}
// This is called on the audioAnalysisTimer
#objc func audioAnalysis(){
writeToBuffer(val: amplitudeTracker.amplitude) // Write an amplitude value to the rolling buffer
let val = getBufferAverage()
onAmplitudeUpdate?(Float(val))
}
// Writes amplitude values to a rolling window buffer, writes to index 0 and pushes the previous values to the right, removes the last value to preserve buffer length.
func writeToBuffer(val: Double) {
for (index, _) in amplitudeBuffer.enumerated() {
if (index == 0) {
amplitudeBuffer.insert(val, at: 0)
_ = amplitudeBuffer.popLast()
}
else if (index < amplitudeBuffer.count-1) {
amplitudeBuffer.rearrange(from: index-1, to: index+1)
}
}
}
// Returns the average of the amplitudeBuffer, resulting in a smoother audio reactivity signal
func getBufferAverage() -> Double {
var avg:Double = 0.0
for val in amplitudeBuffer {
avg = avg + val
}
avg = avg / amplitudeBuffer.count
return avg
}
}