MATLAB - fft, find where it occurs in original data

[masterj]

Hey guys!
For the past few hours I've been trying to find solution to my problem, but unsuccesfully.
The situation is this: I have transformed audio data to fft, found a peak value and then I need to find where it occurs in original data.

My script:
LOAD THE FILE:

[AUDIO_ARRAY1 AUDIO_FS1] = wavread('AAA.WAV');

TRANSFORM IT TO FFT:

AMPLITUDE = abs(fft(AUDIO_ARRAY1));
AMPLITUDE = AMPLITUDE(1 : floor(NUMBER_OF_SAMPLES / 2)); % let's remove mirrored data
FREQUENCY = AUDIO_FS1 * (0 : floor(NUMBER_OF_SAMPLES / 2) - 1) / NUMBER_OF_SAMPLES;

FIND SOME VAL:

if max(AMPLITUDE) == 160
PEAK_VALUE = max(AMPLITUDE);
end

And now I need to find where in AUDIO_ARRAY1 my PEAK_VALUE occurs... Any ideas how to do this?

 

[klystron]

Some psuedo code
do
if current amplitude value < current+1 amplitude value then peak position = current+1 else peak position = current
current ++
while current < array size