AudioFileWriteBytes is taking way too long to do its job - ios

Question

This problem may be a bit too vast and nebulous for this space, but I'll give it a go.
I have an array of samples that I'm trying to write to a .wav file on my iOS and it is taking up to a minute and a half to do. Here is the loop where the drag is occurring:
for (int i=0; i< 1430529; i++) // 1430529 is the length of the array of samples
{
SInt16 sample;
sample = sample_array[i];
audioErr = AudioFileWriteBytes(audioFile, false, sampleCount*2, &bytesToWrite, &sample);
sampleCount++;
}
Any ideas?
EDIT 1
If it helps, this is the code that precedes it:
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
// THIS IS MY BIT TO CONVERT THE LOCATION TO NSSTRING
NSString *filePath = [[NSString alloc]init];
filePath = [NSString stringWithUTF8String:location];
// HERE I WANT TO REMOVE THE FILE NAME FROM THE LOCATION.
NSString *truncatedFilePath = filePath;
truncatedFilePath = [truncatedFilePath stringByReplacingOccurrencesOfString:#"/recordedFile.wav"
// withString:#"/newFile.caf"];
withString:#"/recordedFile.wav"];
NSLog(truncatedFilePath);
NSURL *fileURL = [NSURL fileURLWithPath:truncatedFilePath];
AudioStreamBasicDescription asbd;
memset(&asbd,0, sizeof(asbd));
asbd.mSampleRate = SAMPLE_RATE;
asbd.mFormatID = kAudioFormatLinearPCM;
asbd.mFormatFlags = kLinearPCMFormatFlagIsSignedInteger | kLinearPCMFormatFlagIsPacked;
asbd.mBitsPerChannel = 16;
asbd.mChannelsPerFrame = 1;
asbd.mFramesPerPacket = 1;
asbd.mBytesPerFrame = 2;
asbd.mBytesPerPacket = 2;
AudioFileID audioFile;
OSStatus audioErr = noErr;
audioErr = AudioFileCreateWithURL((CFURLRef)fileURL, kAudioFileWAVEType, &asbd, kAudioFileFlags_EraseFile, &audioFile);
assert (audioErr == noErr);
long sampleCount = 0;
UInt32 bytesToWrite = 2;

Answer 1

Why do you need the loop ? Can't you write all the samples in one go, e.g.
numSamples = 1430529;
bytesToWrite = numSamples * 2;
audioErr = AudioFileWriteBytes(audioFile, false, 0, &bytesToWrite, sample_array);
?

Answer 2

Perhaps the number of bytes you are writing at each call to AudioFileWriteBytes is too small. How large is bytesToWrite?