Humming from GK RB 1001 Mark II hooked up to NEO 410

[Snake357]

I am a novice bass player and I got some gigs lined up next month so I got myself a RB 1001 and a NEO 410 was stoked when I got it but now I am getting this very loud hum and I cant figure out what it is. I am using a Peavey Fury II but I doubt that is the problem since I have used GK products when I rehearse in different studios. Also I am a bit confused with the ohms. The head goes 700 watts at 4 ohms and 460 at 8. Does this mean I am only getting 460 with the NEO?

Any advice would be helpful thank you!