             engine.connect(finalMixer.avAudioNode, to: engine.outputNode)
         }
     }
-	
-	#if os(iOS)
-	private static let cx = CTCallCenter()
-	private static var microphoneLocked: Bool {
-		return cx.currentCalls?.count ?? 0 > 0
-	}
-	#else
-	private static let microphoneLocked = false
-	#endif
 
     // MARK: - Device Management
 

#if !os(tvOS)
import CoreAudioKit
#endif
#if os(iOS)
import CoreTelephony
#endif

import Dispatch


    // Restarts the engine after audio output has been changed, like headphones plugged in.
    @objc fileprivate static func restartEngineAfterRouteChange(_ notification: Notification) {
        DispatchQueue.main.async {
            if shouldBeRunning && !engine.isRunning {
                do {

                    #if !os(macOS)
