trying to give audio input signal to ode but getting inaccurate results

I am giving external input signal to adaptive hopf oscillator and i want to adapt audio input signal frequency. I have done it using ode45 but the sumulation taking too much time and not getting accurate result.

here i am giving fi2 as an input but i am not getting accurate results.

any one has idea how to solve this problem ?

please tell me if there any changes in code .

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function to solve differential equation

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function dz = myeqd(t,y,ti,fi2)

dz = zeros(3,1);

mu=0.7;

r= sqrt(y(1)^2 + y(2)^2);

K=2;

%w=40;

F=interp1(ti,fi2,t);

dz(1)= (mu - r^2)*y(1) - y(3)*y(2) +K*F;

dz(2) = (mu - r^2)*y(2) + y(3)*y(1);

dz(3) = (-K*F) * (y(2)/sqrt(y(1)^2 + y(2)^2));

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main function

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[fi fs]=wavread('sound1'); % /* read file into memory */

fi2 = fi(:,1); % left coloumn vector

tt= 0:1/fs:(length(fi2)-1)/fs; % time vector

ti=tt;

[T,Y]= ode45(@(t,y) myeqd(t,y,ti,fi2),tt,[10;10;10]);

plot (T,Y)

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