That's a LV error and it happens because you are not reading data from the PC buffer fast enough.
In order to prevent this error, you might increase the size of the background acquisition buffer (buffer size), increase the amount of data you read (scans to read), slow down your acquisition rate (scan rate), reduce the number of tasks your computer is performing, return binary data of your "AI Read.VI" (this is a polymorphic VI), or remove any extra processing that is inside the loop of "AI Read.VI".
L Aguila
Applications Engineer
National Instruments