Well, dafishkilla, beat me to the ultimate solution . . . unplug it LOL.
I've found that some pumps are quieter when put on there side. Also, if you are using a gang valve with more than one outlet, you might check to see if you are getting too much backpressure. I leave one of the valves empty and use it to bleed off some of the pressure instead of having all of the air going through one valve.
Hope this helps . . .