Speedy-33 feedback loop

Hi, i'm using speedy-33 as my DSP target and i wish to perform a feedback loop. i tried the example found in the NI website but it shows error that the array size is mismatch.
Does anyone know how the data flows?
Let say when i create an analog input, it is a 1-D array. Inorder to create a feedback loop i need to create an array of known size 1st, am i right to say that?? From there onwards, wat are some of the ways that i can can my array size or when do i need to alter my array?
Can anyone pls help??
Thanks

Hi steven,
Thanks for the reply,
Using labview 8.2, DSP target speedy-33
Currently i'm trying to get a feed back from my sample delay function then add back to my signal to create a reverberation effect.
problem
1)the waveform i see from my waveformchart are square wave.
2)I try to set my frame size at 1024 but the programm just run for a few sec and stop.
3)my audio signal sounds like transformer singing!!
can someone help me point out where my problem lies on??
Thanks in advance.
Attachments:
Feedback using for loop.vi ‏49 KB

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Tommy,
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Sistema dinamico6.vi ‏462 KB

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