Hey guys, I have a bit of a weird issue, want to see if anyone can help me troubleshoot it. First, here is the current setup of my rig: Gallien Kruger 2001RBP preamp (chain out 1/4") to XLR input 1 of a Stewart World 2.1 World 2.1 Banana Plugs to: Carvin RL210T and Carvin RL115 (1/4" inputs) I also have the XLR Direct out of my GK going to the mixer for the PA. Heres my issue: There is a very audible buzz coming from my speakers. I noticed a couple things: 1: If I turn off my stewart, the buzzing will continue (over the PA) if I have the switch on the back of the GK set to Post EQ on the direct out. If it change it to pre-eq, the buzzing stops on the PA speakers. When I turn the Stewart back on, the buzzing continues out of my bass amp speakers but still remains silent on the PA speakers. 2. On my bass amp, the "Woofer" knob seems to be what is affecting it, but obviously that is most of the volume anyway (you just get the tweeter otherwise). Any things I can try? I thought about power issues, and I've tried some outlets in the same room, but I haven't tried it in a completely separate room yet. Unfortunately I'm not near it right now to try anything, but I will be tonight.