求解答这个报错不知道怎么回事？

代码如下

clear
Fs = 44100 ; 
nBits = 16 ; 
nChannels = 2 ; 
ID = -1;
recObj = audiorecorder(Fs,nBits,nChannels,ID);
%用麦克风采集一个时长为五秒钟的演讲样本
disp('Start speaking.')
recordblocking(recObj,5);
disp('End of Recording.');

%冲击响应函数h(t) 
 a0=1;%反射系数
 a1=0.8;
 a2=0.6;
 T=1/Fs;
 t=0:T:3;
 h=a0*my_delta(t-0.2)+a1*my_delta(t-0.4)+a2*my_delta(t-0.6);
 %卷积得到回音
 
 y=conv(recObj,h);
 y=y';
 player = audioplayer(y,fs);
 play(player);%播放回音
 subplot(2,1,1);
 plot(recObj);%画原始音
 title('原始音');
 subplot(2,1,2);
 plot(y(1:length(y)));%画回音
 title('经过回音系统');

你好！
你所示代码的第21行改成下面两行即可

y = getaudiodata(recObj);
y=conv(y,h);