title: AudioKit AKFFTTap does not fill fftData array above bin 512
body: <p>I want to increase the FFT resolution and have more bins per signal analysed.
  When i leave the fftSize and all buffer lengths at default in AKSettings i get a 512 bin fft, the fftData array has all of the 512 array elements filled out.</p>
  <p>From this I am able to get real and imag parts, magnitudes and it works.</p>
  <p>If i setup the ffttap with a higher fftsize like so
  <code>fftTap = AKFFTTap.init(mic, fftSize: .huge)</code></p>
  <p>I get an increased fftData array size, the fftData.count is 1024, but only 512 array elements are filled, everything past fftData[511] are 0.0s.</p>
  <p>Am I missing some specific configuration step when I want to increase the FFT resolution?</p>
  <p>Anybody with some input would be very helpful, thanks!</p>