Atheros AR9485 slow connection

[brunomaximom at openmailbox.org]

Hi all, I'm using FreeBSD 12-CURRENT and I get a very slow speed 
connection since when I was in FreeBSD 10-RELEASE. I have a AR9485 
wireless card and getting =~ 150kB/s, but in Linux I get the real paid 
speed =~ 2MB/s.

Any idea?

Thanks.