Decode AAC to PCM format using AVAudioConverter Swift

How convert AAC to PCM using AVAudioConverter, AVAudioCompressedBuffer and AVAudioPCMBuffer on Swift?

On WWDC 2015, 507 Session was said, that AVAudioConverter can encode and decode PCM buffer, was showed encode example, but wasn't showed examples with decoding. I tried decode, and something doesn't work. I don't know what:(

Calls:

//buffer - it's AVAudioPCMBuffer from AVAudioInputNode(AVAudioEngine)
let aacBuffer = AudioBufferConverter.convertToAAC(from: buffer, error: nil) //has data
let data = Data(bytes: aacBuffer!.data, count: Int(aacBuffer!.byteLength)) //has data
let aacReverseBuffer = AudioBufferConverter.convertToAAC(from: data) //has data
let pcmReverseBuffer = AudioBufferConverter.convertToPCM(from: aacBuffer2!, error: nil) //zeros data. data object exist, but filled by zeros

It's code for converting:

class AudioBufferFormatHelper {

    static func PCMFormat() -> AVAudioFormat? {

        return AVAudioFormat(commonFormat: .pcmFormatFloat32, sampleRate: 44100, channels: 1, interleaved: false)
    }

    static func AACFormat() -> AVAudioFormat? {

        var outDesc = AudioStreamBasicDescription(
                mSampleRate: 44100,
                mFormatID: kAudioFormatMPEG4AAC,
                mFormatFlags: 0,
                mBytesPerPacket: 0,
                mFramesPerPacket: 0,
                mBytesPerFrame: 0,
                mChannelsPerFrame: 1,
                mBitsPerChannel: 0,
                mReserved: 0)
        let outFormat = AVAudioFormat(streamDescription: &outDesc)
        return outFormat
    }
}

class AudioBufferConverter {

    static func convertToAAC(from buffer: AVAudioBuffer, error outError: NSErrorPointer) -> AVAudioCompressedBuffer? {

        let outputFormat = AudioBufferFormatHelper.AACFormat()
        let outBuffer = AVAudioCompressedBuffer(format: outputFormat!, packetCapacity: 8, maximumPacketSize: 768)

        self.convert(from: buffer, to: outBuffer, error: outError)

        return outBuffer
    }

    static func convertToPCM(from buffer: AVAudioBuffer, error outError: NSErrorPointer) -> AVAudioPCMBuffer? {

        let outputFormat = AudioBufferFormatHelper.PCMFormat()
        guard let outBuffer = AVAudioPCMBuffer(pcmFormat: outputFormat!, frameCapacity: 4410) else {
            return nil
        }

        outBuffer.frameLength = 4410
        self.convert(from: buffer, to: outBuffer, error: outError)

        return outBuffer
    }

    static func convertToAAC(from data: Data) -> AVAudioCompressedBuffer? {

        let nsData = NSData(data: data)
        let inputFormat = AudioBufferFormatHelper.AACFormat()
        let buffer = AVAudioCompressedBuffer(format: inputFormat!, packetCapacity: 8, maximumPacketSize: 768)
        buffer.byteLength = UInt32(data.count)
        buffer.packetCount = 8

        buffer.data.copyMemory(from: nsData.bytes, byteCount: nsData.length)
        buffer.packetDescriptions!.pointee.mDataByteSize = 4

        return buffer
    }

    private static func convert(from sourceBuffer: AVAudioBuffer, to destinationBuffer: AVAudioBuffer, error outError: NSErrorPointer) {

        //init converter
        let inputFormat = sourceBuffer.format
        let outputFormat = destinationBuffer.format
        let converter = AVAudioConverter(from: inputFormat, to: outputFormat)

        converter!.bitRate = 32000

        let inputBlock : AVAudioConverterInputBlock = { inNumPackets, outStatus in

            outStatus.pointee = AVAudioConverterInputStatus.haveData
            return sourceBuffer
        }

        _ = converter!.convert(to: destinationBuffer, error: outError, withInputFrom: inputBlock)
    }
}

In result AVAudioPCMBuffer has data with zeros. And in messages I see errors:

AACDecoder.cpp:192:Deserialize:  Unmatched number of channel elements in payload
AACDecoder.cpp:220:DecodeFrame:  Error deserializing packet
[ac] ACMP4AACBaseDecoder.cpp:1337:ProduceOutputBufferList: (0x14f81b840) Error decoding packet 1: err = -1, packet length: 0
AACDecoder.cpp:192:Deserialize:  Unmatched number of channel elements in payload
AACDecoder.cpp:220:DecodeFrame:  Error deserializing packet
[ac] ACMP4AACBaseDecoder.cpp:1337:ProduceOutputBufferList: (0x14f81b840) Error decoding packet 3: err = -1, packet length: 0
AACDecoder.cpp:192:Deserialize:  Unmatched number of channel elements in payload
AACDecoder.cpp:220:DecodeFrame:  Error deserializing packet
[ac] ACMP4AACBaseDecoder.cpp:1337:ProduceOutputBufferList: (0x14f81b840) Error decoding packet 5: err = -1, packet length: 0
AACDecoder.cpp:192:Deserialize:  Unmatched number of channel elements in payload
AACDecoder.cpp:220:DecodeFrame:  Error deserializing packet
[ac] ACMP4AACBaseDecoder.cpp:1337:ProduceOutputBufferList: (0x14f81b840) Error decoding packet 7: err = -1, packet length: 0

from Decode AAC to PCM format using AVAudioConverter Swift