My machine has been running for about 4 months. One driver was DOA. Today, another may have bitten the dust...in the middle of a job. That's a 60% success rate in less than half of a year. I start up for the first time of the day. I try to home and the A axis isn't moving. All of my signals are fine. The wiring is intact. There is no dust or foreign objects anywhere. The steeper works fine on any other channel. Any other stepper fails on the A channel. Instead of being locked, the connected stepper can now be rotated by hand. It does not rotate as easily as a completely disconnected stepper, but it still rotates. So tell me, is this normal? Oh and my green led is out on that driver alone.