#1
I am using a friends russian big muff and when i use it as the only pedal in the chain (the problem happens when other pedals are connected to) there is this awful background noise, and lots of feedback. It sounds really bad.

I know fuzz pedals are suppose to simulate speakers with holes poked in them but is this suppose to happen? Any info regarding my gear can be found in my sig.
#3
Hmm, there might be something loose in the circuit, change the battery aswell.

My Big Muff sucks tone when it's first in the chain, but when it's not everything's fine.
"Breathe, breathe in the air
Don't be afraid to care"

Fender Strat/Tokai LS80>few pedals>Orange Rocker 30
#4
This is so much sucking tone, I guess it is just the loud high pitched background noise (no, it does not sound like feedback, more like static) that keeps alternating between what sounds like feedback and static.
#5
Use your guitars humbucker, if you have the sustain all the way up you're bound to get loads of feedback.
"You can practice to attain knowledge, but you can't practice to attain wisdom." - Herbie Hancock