hey. i have a guild "thunderbass" amp. i think it's about ten years old. i've had it here in my basement for about 4 months. this problem has only started happening a month and a half ago. in mostly any position of my bass i get this loud humming noise. i have to position it another way to stop it and it's really hard to play. i'm absolutely sure it's not my bass cause i got it checked out and there was absolutely nothing wrong with it. and it's not the cord cause i tried a whole buncha cords and it happens with all of them. i asked someone about it and he said it might be because i have a flourescent light across the room and it's interfering. is this the problem?