Help me Mr Wizard! My Genz Benz Streamliner has just developed a tremendous buzzing! I've tried it with both my Stingray and my Godin A4. It's a horrible noise, like a 60 cycle hum. It only makes the noise when I have something plugged in (Bass, Mandolin, Acoustic guitar, Hammer Dulcimer) I've tried two cables, Road Hog 10' and a Mogami Gold 8' and it's the same with each. If I touch a string, the bridge, the amp, or anything metal, the noise goes away. I use this amp all day long. I work from home, and I have my MP3 player connected to the AUX in (it doesn't make the noise when I'm listening to music.) Several times a day I'll take a break, plug an instrument in and play along with a song. It's been fine all day, and it just started tonight. What should I do? Is there another thing I can do to test? My guess is there's a bad ground in the pre-amp. I don't know what else I can do to test it. I really don't want to be without this thing, I use it 16 hours a day! What do you recommend?