What is the "miscellaneous" grey slice?
The grey slice contains valid packet data that is too small to give it's own slice, to avoid having a lot of tiny slices. Instead of drawing a lot of tiny slices, Eye P.A. aggregates all of the information into one "miscellaneous" slice.
The slice is colored grey because it might contain management, control, and data frames.
To view the data in the grey slice, click on it's parent slice.