Crashes when I use my audio.m4a file replace VoiceRecordingWeb.m4a https://github.com/FSilver/Resource/blob/main/audio.m4a

[FSilver]

1. func testConversionRoundTrip() {
   let src = Bundle.main.url(forResource: "VoiceRecordingWeb", withExtension: "m4a")!

func testConversionRoundTrip() {
let src = Bundle.main.url(forResource: "audio", withExtension: "m4a")!

2. creashed
   encoder = opus_encoder_create(opusRate, pcmChannels, application.rawValue, &status)
   OGGEncoder.swift:80: Fatal error: Unexpectedly found nil while implicitly unwrapping an Optional value

3. AVAudioRecorder
   [
   AVFormatIDKey: NSNumber(value: kAudioFormatMPEG4AAC),
   AVNumberOfChannelsKey: 1,
   AVEncoderAudioQualityKey : AVAudioQuality.low.rawValue,
   AVLinearPCMBitDepthKey : 16,
   AVSampleRateKey : 44100.0
   ]
   use this setting to create audio.m4a
   文件地址 https://github.com/FSilver/Resource/blob/main/audio.m4a

[FSilver]

must be 48HZ