No, don't ignore it. I don't know what you should modify though because it shouldn't be there.
I'd say either you added a sysctl/tunable that you shouldn't be doing and you're just randomly adding stuff hoping it'll work or something related to your hardware is just not right with FreeNAS.
Yeah, well I don't feel comfortable enough to go about fiddling with 'tunables' - so this is a fresh install off of the ISO. Happened three different installs, and the install is onto a USB flash drive.