Visual Analog data collection problem

We’re using Visual Analog to communicate with a HSC-ADC-EVALB-DCZ board, capturing samples from an AD9283. The Visual Analog file simply takes the output of the ADC, through an Input Formatter and into a Pattern Saver. This has worked well with relatively small sample sizes. However, when we raise the sample size to the max of 8.3M, it seems I only get 32768 unique samples, the remaining lines in the file are duplicates of the last point sampled.