You said its still there when you pull the rcas. From the amp or from the head unit or the 360? alot of 360s cause noise.
pull the rcas from the amps. All of them. Is the noise still there?
If so Id start unhooking speakers. One at at ime til the noise goes away. When you find hte one that makes the noise go away( if you do) start looking into it. Could be the speaker wire is touching it. could be that you have a screw that you mounted it with grounding out on the frame. A factory wire could be touching a speaker Could be you nicked the speaker line putting them in. lots of things. IF the noise is still there when you unhook all the speakers you can rule them out.