Getting Buzzing Noise With My Mesa Tremoverb And Boss NS-2 Noise Gate?

[Charvel1975]

So our band had practice last night and I hooked up my Mesa tremoverb head, Marshall 1960A and Boss NS-2 Noise Gate and was getting a lot of feedback and buzzing noise? On the red channel I only had the gain at about 1 o'clock and the guitar I was using was our drummers Washburn 7-string with a seymour duncan jb in the bridge and a 59 in the neck and it has the 5-way switch. I even switched the 3-way polarity switch on the back of the Mesa and that didn't help?