Audio CMSampleBuffer volume change in Swift

Question

I am trying to record a video with AVAssetwriter. Now want to control volume for my final output video file. Any Help?

Solutions I had tried:-

1. self.avAssetInputAudio?.preferredVolume = 0.2 //The value for this property should typically be in the range of 0.0 to 1.0. (which is equivalent to a “normal” volume level) https://developer.apple.com/documentation/avfoundation/avassetwriterinput/1389949-preferredvolume Output:- No change in volume level in the output file.

2.Processing Audio with CMSampleBuffer

    func processSampleBuffer(scale: Float, sampleBuffer: CMSampleBuffer, writerInput: AVAssetWriterInput) -> Bool {
    guard let blockBuffer = CMSampleBufferGetDataBuffer(sampleBuffer) else {
        return false
    }
    let length = CMBlockBufferGetDataLength(blockBuffer)
    var sampleBytes = UnsafeMutablePointer<Int16>.allocate(capacity: length)
    defer { sampleBytes.deallocate(capacity: length) }
    
    guard checkStatus(CMBlockBufferCopyDataBytes(blockBuffer, 0, length, sampleBytes), message: "Copying block buffer") else {
        return false
    }
    
    (0..<length).forEach { index in
        let ptr = sampleBytes + index
        let scaledValue = Float(ptr.pointee) * scale
        let processedValue = Int16(max(min(scaledValue, Float(Int16.max)), Float(Int16.min)))
        ptr.pointee = processedValue
    }
    
    guard checkStatus(CMBlockBufferReplaceDataBytes(sampleBytes, blockBuffer, 0, length), message: "Replacing data bytes in block buffer") else { return false }
    assert(CMSampleBufferIsValid(sampleBuffer))
    return writerInput.append(sampleBuffer)
}

func checkStatus(_ status: OSStatus, message: String) -> Bool {
    assert(kCMBlockBuferNoErr == noErr)
    if status != noErr {
        debugPrint("Error: \(message) [\(status)]")
    }
    return status == noErr
}

output:- Final audio is choppy and noisy.