Remove double axis-label

Does anybody know how I can remove the original axis-numbers "5", "10" etc from the x-axis in the figure that is generated by the commands below? As you can see, the commands produce a double axis-label. I guess it happends because both series has its own x-axis and that the commands only replaces one of these axis so that one is left in addition to the new axis. I wish only to have one x-axis label and that is the new one.

A = rand(43,1);
B = rand(43,1);

Aar = {'2003K1','2003K2', '2003K3',  '2003K4',  '2004K1',  '2004K2',  '2004K3',  '2004K4',  '2005K1',  '2005K2',  '2005K3',  '2005K4',  '2006K1',  '2006K2',  '2006K3',  '2006K4',  '2007K1',  '2007K2',  '2007K3',  '2007K4',  '2008K1',  '2008K2',  '2008K3',  '2008K4',  '2009K1',  '2009K2',  '2009K3',  '2009K4',  '2010K1',  '2010K2',  '2010K3',  '2010K4',  '2011K1',  '2011K2',  '2011K3',  '2011K4',  '2012K1',  '2012K2',  '2012K3',  '2012K4',  '2013K1', '2013K2', '2013K3'}
start=1; stop =length(Aar);
a=1; b=1+stop-start; intervall = 1; out=a:intervall:b;
[AX,H1,H2] = plotyy(out,A(start:stop),out,B(start:stop),'plot');
set(get(AX(1),'Ylabel'),'String','A','Color', [0 0 0],'linewidth', 3) 
set(get(AX(2),'Ylabel'),'String','B','Color', [0 0 0],'linewidth', 3) 
set(H1,'Color', [0 1 0]);
set(H2,'Color', [1 0 1]);
intervall2 = 4; out2=a:intervall2:b; 
set(gca, 'XTick',[out2])
set(gca, 'XTickLabel',Aar(start:intervall2:stop))

Answer 1

[Karl]

The folollowing two lines inserted before the two last lines in the script above made it work:

set(AX, 'xTickLabel','') 
linkprop(AX,{'Xlim','XTickLabel','Xtick'});