Why is the accuracy of imufilter positional?

I recorded raw data from 9 sensors with multiple motion sequences. I imported the data into matlab and fused it with imufilter, and below is the result (for one sensor, but it happens for all sensors). The last position in this sequence is associated with significant noise/fluctuation. I have another data series representing different motion and the same fluctuation is happening when the same orientation is being logged for all sensors. Does anyone know the source of this error and how to overcome it? I believe it occurs during the imufilter sensor fusion process, because the raw data looks fine.