I was moving the monitor...perhaps stretched it a bit too far and my PowerMac G4 shut down. The connection of the monitor to the tower came off so I plugged it back in and my subwoofer started to make a steady thudding sound. The G4 would not start up and I reset the CUDA/PMU (perhaps unnecessarily) and disconnected the monitor from the tower. The tower is now able to power on independently of the monitor....but as soon as I hook up my monitor, it shuts the whole thing down and the thudding sound from the subwoofer comes back. The sound is not present when the monitor is disconnected from the G4 which leads me to think that my problem is with the monitor. I'm not sure what I could have upset or broken....any advice will be greatly appreciated.