How to populate AudioStreamBasicDescription for AMR_WB?

Hey I am trying to decode AMR_WB audio on iOS, for this I am using the below settings

    var asbd = AudioStreamBasicDescription()
    asbd.mSampleRate = Float64(sampleRate)
    asbd.mFormatID = kAudioFormatAMR_WB
    asbd.mFormatFlags = 0
    asbd.mFramesPerPacket = 320
    asbd.mChannelsPerFrame = UInt32(channels)
    asbd.mBitsPerChannel = 16 * UInt32(MemoryLayout<UInt8>.size)
    asbd.mReserved = 0
    asbd.mBytesPerFrame = 2
    asbd.mBytesPerPacket = asbd.mBytesPerFrame * asbd.mFramesPerPacket
    let _audioFormat = AVAudioFormat(streamDescription: &asbd)!
    return _audioFormat

But I encounter the error as follows:

Error Domain=AVFoundationErrorDomain Code=-11800 "The operation could not be completed" 
UserInfo={NSLocalizedFailureReason=An unknown error occurred (1885696621), 
NSLocalizedDescription=The operation could not be completed, 
NSUnderlyingError=0x283fb1920 {Error Domain=NSOSStatusErrorDomain Code=1885696621 "(null)" 
UserInfo={AVErrorFourCharCode='perm'}}}

Now as per the documentation found here, it looks to be supported but I am unable what permission to give to the application for this to work. Any help will be appreciated.