I had my bass set up a month ago. I've been playing it every day and it's been fine. I plugged it in yesterday and I was disappointed to hear a funny buzzing sound on my open G string. This buzz is different from normal buzz. Normally, a buzz comes from the nut or one of the springs on the bridge rattling around, or the tuning keys. And usually I can hear the buzz when my bass is unplugged. But this time, I only hear it when I'm plugged in. So, I thought the problem is not mechanical. It's the electronics. But why does it only happen when I play the open G string? And it sounds more like a buzz then a distortion. Help?