I am having a spot of bother with my rig misbehaving and making weird noises, and was wondering if anyone could help me out.
Here is a diagram of my setup:

I have the tuner pedal set up so that it mutes when I step on it (i.e. it is silent while I'm tuning my guitar, at least in theory). However, when I do this, I get a horrible buzzing noise out of my amp. The noise is alleviated somewhat by switching off the compressor, but is still there, albeit a bit quieter.
Now, what I don't understand (possibly because I'm an idiot) is:
1. What is causing this noise – am I doing something idiotic somewhere in the signal chain?
2. Why the noise isn't dealt with by the noise suppressor, since the source of it (seemingly the tuner) would appear to be in the NS-2's loop.
Anyone have any ideas?
EDIT: I changed the image so I've got the name of my chorus pedal right this time.