[Pdelcast]

Basso --

We see (rarely) a failure like that -- often they are caused by a cracked resistor or capacitor (or solder ball stuck under a chip, or bad solder joint, etc.) that was missed during testing, and fails shortly after.

What we call that behavior is "two phasing" -- means that two phases are working, but one either isn't driving, or has a problem with the back-EMF circuit.

We'll make sure you get your replacement ASAP.