I just got my new rig last week (avatar 4X10 and hartke 3500) and Ive been using it with my jazz bass at my house by myself and it was fine. Today i used it with the band for the first time and i got a terrible static/farting/distorted noise on top of the bass's sound (you could hear the bass, but there was added sound). The only differences between my setup at practice and my house was my house was bass-->cord-->rig. At practice it was same bass--->different cord-->boss ob3--->different cord--->boss ceb3--->different cord--->rig. Also, at practice i had everything pluged into a power strip. It didnt make this noise constantly, it came and went. Can someone help me?