# How to find and fix the delay of a modulation

I am creating a model in MATLAB to simulate power line communication, but I found a problem. I'm very new to the DSP area, I get my code below from a MATLAB example.

    %mod/demod GMSK
hMod = comm.GMSKModulator('BitInput', true, 'InitialPhaseOffset', pi/4);
hAWGN = comm.AWGNChannel('NoiseMethod','Signal to noise ratio (SNR)','SNR',0);
hDemod = comm.GMSKDemodulator('BitOutput', true,'InitialPhaseOffset', pi/4);
% Error calculator by viterbi algortim
for counter = 1:10
% mod 10 words of 8-bits
data = randi([0 1],8,1);
modSignal = step(hMod, data);
noisySignal = step(hAWGN, modSignal);

• How can I discover the delay of my mod/demod process and fix that? Basically what I saw debugging the code was: my output (receivedData) only start to receive the data after the third iterarion of the for-loop.
First data send -> 11110000
First output data in the vector -> 11110000