Same issue as MANY others listed here. I trusted the GE brand and loved the Cafe line, so we splurged on the drawer microwave and now have the sparking issue in the same back left corner. You can clearly see many other reviews and examples of this, the back left corner has a wear mark where the bearing is rubbing and exposed metal is causing the sparks. This is not from abuse, this is normal open/close operation and started under 1 year, but we didn't think much of it and it stopped for a while, but now is back and unusable.