So is it like a hiccup in an otherwise smooth reading? Is it just at one given Hz or at different values? Are you using Link to compensate for the evo maf?
If you are using Link, have you tried to make adjustments to the choppy areas? I know they have a selection for the evo maf, but maybe it not an accurate fit for your maf/setup. Also I thought there were more than one type or number of evo 8 maf, this could be a reason why the evo 8 maf selection in link might not work for everyone.
It could just be the maf is messed up. Did it happen immediately when you put in the maf or is it something that just came up? Have you verified that you don't experience the same choppy readings on a stock maf?
I had an evo 8 maf in my car with link using a plug and play adapter and it didn't idle very well and it would stall a lot when I disengaged the clutch so I just switched to SD.