You may just hearing inherent noise that is from the pedal. Might I ask what your setting are? If you have the drive turned up high and your amp is not so clean all of that is amplified noise. I haven't finished my RAT Clone yet but I have finished the Llama clone as well as the TS aka Rhino clone and if the drive is up loud, noise is prominent.
Thats good to know. My Llama clone has the noise but not nearly as much as the Rat and I do have the drive up pretty high. It just seems like there is more noise there then say the Box of War with the drive up high.
Are you using a battery or power supply? If your using a power supply you can get noise coupling from the supply or the pedals that are connected to the supply. See if a battery solves the noise problem as a way of isolating.So I have built 2 pedals from general guitar gadget kits and they both sound great except they both have some noise when I am not playing. And the Rat clone gets real noisy if I kick on a second dirt pedal. Any suggestions on where I may have screwed up?
All depends on the chip the box is using. The RAT clone while it does not use the old LM308, still has some inherent noise as all chips do. Generally the newer the chip the quieter it may be. Also depends on the circuit config. For drive pedals though, you will get noise. Some suggestions to reduce noise are cables. This is the part of the big debate regarding cable quality. Bottom line, I use great cables and don't get noise like other do. How noisy are your pickups? If you have high gain pickups, you will get added noise than lower gain pickups. An example of what I consider a low gain pickup is a 59 PAF style. Lastly is your amp. How is it setup. Is it setup purely clean, mild gain, crunch or full on distortion. From left to right the noise floor increases before you even step on a pedal.
Are you using a battery or power supply? If your using a power supply you can get noise coupling from the supply or the pedals that are connected to the supply. See if a battery solves the noise problem as a way of isolating.
I also agree with the other comments. A distortion petal is a high gain device and will have a fair amount of hiss as you raise the gain typically above half.