So recently I have been have major issues with my Cupcake CNC. Power issues, then blown MOSFET's, fried SD cards, dead H-Bridges and serial communications. I have been troubleshooting with Makerbot's Operater group, and Makerbot themselves. I found out that I could get my extruder controller RMAed for the H-Bridges and blown MOSFET's. So, funny story right... Today I was taking off my extruder controller to send it in and well wouldn't ya know, there was a beautiful little spider web across some of the pins on my extruder controller. I guess spiders like 3D printing too!