I have an interesting problem. I do consulting for a local cabinet shop that uses a C version Carvewright. I brought it home for testing and it keeps getting an intermittent "Power Fluctuation" error message that allows it to continue carving by pressing any key. I changed the power supply and I'm still getting the error message. About 40% into the carving it will halt and display an error message that states "the data card needs to be re-flashed. I did that a couple of times and even bought a new data card with the same results. My other machine reads the cards just fine. Extension cords are not an issue. 30 amp circuit and power cord split into two 20 amp gfci plugs on the end and my other Carvewright has no issues using the same setup. The only thing I can think of is that the controller is bad but, I'm open to suggestions. I really hope it isn't the controller as they will probably scrap the machine before spending another $300.00 on what has proven to be an extremely problematic POS. (their terminology)