One of our 7890 Simdist GCs has been having continuous problems with oven shroud failures. Upon replacing with a new shroud, the temperatures read correctly, the oven heats at a normal rate until it gets to approximately 75 degrees, and then it plateaus, at which point it no longer heats. Checking the continuity of the shroud power cables shows an open, and visual inspection shows that the coil has snapped. we are using 115V oven shrouds and have not had any luck narrowing down the root cause. Is this an issue with a logic board? or a power board? or an issue with the shrouds themselves?