Strange problem I think.  My Y axis is an Aerotech BA30 amp with B500 brushless DC motor. When auto tuning with WSDK I get strange sets of parameters. But I can get it to run well by giving Galil commands from the terminal. Nice moves and no noise although if I check settling time it's terrible and when I run those params in manual to see what the scope says, it looks bad. The funny part is that when I start Mach and make a move with the Y axis, it starts humming. The moves seem to be correct and it runs programs fine but always hums. When I shut down Mach, the humming goes away. Any clues as to why this happens? It seems like the Galil plugin is doing something to make the motor hum and unstable.

Thanks, Allen