iOS MPVolumeView Not Responding to Hardware Volume Changes After Audio Streaming Starts

I've integrated MPVolumeView into my view, and it correctly responds to hardware volume changes as expected. However, once I initiate audio streaming using AVAudioEngine to capture microphone audio and AudioUnit for decoding, the MPVolumeView ceases to reflect changes made using the hardware volume buttons. Additionally, even when I adjust the volume using the slider on MPVolumeView, it doesn't change the system volume. Has anyone else encountered this issue? What might be causing MPVolumeView to stop responding to hardware volume changes once streaming starts?

For the AVAudioSession.Mode, I use the default setting because using .voiceChat prevents MPVolumeView update from device volume changes permanently.

let session = AVAudioSession.sharedInstance()
do {
    try session.setCategory(.playAndRecord, options: [.allowBluetooth])
    try session.setActive(true)
} catch {
   print(error.localizedDescription)
}