So you can see the methods this plugin uses to combat hacks. Long story short, it spawns invisible squids to detect forcefield/aura etc, and spawns invisible players to combat tracers/maphacks.
This only happens when you enter no-clip mode.
Maybe there's a way around this?
I wrote to the author too, probably best solved from his end: http://www.spigotmc.org/threads/antiaura-hack-blocker-v5-0-paid.31675/page-138#post-800692

Has this been fixed yet?

Untested by me.

I don't know, the plugin wont load #50

You cannot hide an invisible entity from the players in vanilla spectator mode (3), so this cannot be solved on our side.

Keep me updated on this. Being a premium resource I can't really do anything about this...
I never saw that anti-cheat plugin before, it sounds pretty creative ;)

Yeah, it seems to be the most effective one, eventually you can mail me for a version so you can test :)

Okay, but I think it might be easier for the author of AntiAura to do the
fix using the API.

Yep, I think that is the easiest solution too.

Hmm, it doesn't seem to happen every time (maybe because I updated AA?).