diff --git a/ofdm/ofdm_rx.m b/ofdm/ofdm_rx.m
index 79c35de..dd93da7 100644
--- a/ofdm/ofdm_rx.m
+++ b/ofdm/ofdm_rx.m
@@ -72,6 +72,7 @@ equalizer = struct('Z', 0, 'sync_counter', 20, 'sync', 0, 'started', 0, 's', 0,
 H_syms = [];
 H_pilots = [];
 H_ = [];
+df_track = 1000;
 df_track_ = [];
 
 symbols_per_frame = ofdm_drm_params.nspf;
@@ -109,7 +110,7 @@ while(fileRemain > fileChunkSize)
 	if (~isModePassband)
 	    xwav = xwav(:, 1) + j*xwav(:, 2);
 	end
-%	xwav = xwav - mean(xwav);
+	xwav = xwav - mean(xwav);
 
 	x = xwav.*exp(-j*(2*pi*omega_xwav*(0:fileChunkSize-1)' + phi_xwav)); 
 	phi_xwav = mod(phi_xwav + 2*pi*omega_xwav*fileChunkSize, 2*pi);
@@ -119,7 +120,7 @@ while(fileRemain > fileChunkSize)
 	end
 
 	% add noise
-	x = awgn(x, SNR, 'measured');
+	x = awgn(x, SNR);
 	
 	if (isModePassband)
 		[x, filter_z] = filter(filter_h, 1, x, filter_z);
@@ -157,7 +158,7 @@ while(fileRemain > fileChunkSize)
 	end
 	
 	% Integer CFO coarse
-	if (timingCoarse.sync) && (~cfoCoarseInteger.sync)
+	if (timingCoarse.sync) & (~cfoCoarseInteger.sync)
 		if (~cfoCoarseInteger.started)
 			cfoCoarseInteger.started = 1;
 			fprintf('Coarse integer CFO acquisition');
@@ -181,7 +182,7 @@ while(fileRemain > fileChunkSize)
 	end
 	
 	% Fractional CFO coarse
-	if (cfoCoarseInteger.sync) && (~cfoCoarseFractional.sync)
+	if (cfoCoarseInteger.sync) & (~cfoCoarseFractional.sync)
 		if (~cfoCoarseFractional.started)
 			cfoCoarseFractional.started = 1;
 			fprintf('Coarse fractional CFO acquisition');
@@ -227,15 +228,19 @@ while(fileRemain > fileChunkSize)
 				Z = cfoFine.Xlast .* conj(X);
 				cfoFine.err = kn*angle(Z(bin_pilot));
 				cfoFine.err_ = [cfoFine.err_ cfoFine.err];
-				
-				if (abs(cfoFine.df) > 0.001)
+
+				if cfoFine.sync
+					cfoFine.df = cfoFine.df + 0.1*df_track;
+				else
 					cfoFine.df = cfoFine.df + 0.1*mean(cfoFine.err(cfoFine.bin_track));
-				elseif ~cfoFine.sync
+				end
+				
+				if (abs(df_track) < 0.1) & (cfoFine.sync == 0)
 					if cfoFine.sync_counter > 0
 						cfoFine.sync_counter = cfoFine.sync_counter - 1;
 					else
 						cfoFine.sync = 1;
-						fprintf('Enter fine tracking mode\n');
+						fprintf('Enter fine tracking mode at frame %d\n', equalizer.kk);
 					end
 				end
 				cfoFine.df_ = [cfoFine.df_ cfoFine.df];
@@ -305,7 +310,7 @@ while(fileRemain > fileChunkSize)
 					H_pilots = (H_gain)*W_pilots{equalizer.n+1};
 
 					% Get the correctly delayed symbols
-					Z = buf_Z.readAt(N, -N*symbols_to_delay);
+					Z = buf_Z.readAt(N, -N*(symbols_to_delay+1));
 					sym = Z(carrier_indexes).';
 
 					% Get the correctly delayed raw channel estimate
@@ -314,7 +319,6 @@ while(fileRemain > fileChunkSize)
 					% get frequency error
 					% correlate wiener filtered channel with raw estimate
 					df_track = fs/(2*pi*N)*angle(H_pilots * Hr' + equalizer.eps_abs_h);
-					cfoFine.df = cfoFine.df + 0.01*df_track;
 					df_track_ = [df_track_ df_track];
 
 					% check for too small values
@@ -383,7 +387,7 @@ subplot(3, 1, 1)
 plot(0:length(cfoCoarseFractional.df_)-1, cfoCoarseFractional.df_); grid; title('df_{coarse} (Acquisition)')
 
 subplot(3, 1, 2)
-plot(0:length(cfoFine.df_)-1, cfoFine.df_); grid; title('df_{fine} (Acquisition)')
+plot(0:length(cfoFine.df_)-1, cfoFine.df_, 0:length(df_track_)-1, df_track_); grid; title('df_{fine} (Acquisition), df_{track}')
 
 subplot(3, 1, 3)
 plot(0:length(cfoFine.err_.')-1, cfoFine.err_.'); grid; title('Error(df_{fine}) (Acquisition)')
@@ -403,8 +407,5 @@ wavwrite(y,fs4,nbits,'rx_y.wav');
 
 end
 
-figure;
-plot(df_track_); grid; title('df_{track}');
-
 function Y = spec_order(N, X)
     Y = [X(N/2+1:N)' X(1:N/2)']';