spcomputing:
Cables are just part of the troubleshooting listDon't give up. For some unknown reason, the Mega2560's 16u2 is very sensitive and may need reprogramming from time to time (Not the case with the Uno 16u2). Do you have any programmers or another Arduino?
Thanks for the encouragement. I need it to be a mega as i need to have a ramps 1.4 shield to run a reprap 3d printer. Ill up date my osx to 10.6.0 and see how that goes. This is my only arduino.
What is a programmer in this context?