Hi Dave, thanks for inquiring. After contacting the folks at Sandbox, they agreed to send me a new temperature gauge, which arrived from Taiwan within 2 days, with a Youtube video on how to change it. It was easy enough to replace, the instructions were clear and the the internal design of the R2 is clean and easy to work with. After changing the temperature line, I started a new roast cycle, same one as before 550gr Dark Roast with 500 gr of coffee. The change in temperature gauge improved things marginally. Still could not reach the proper temp for 1st crack. Contacted Sandbox again, they were able to consult my roasting history and concluded something else was defective with the R2. They immediately arranged for a FedEx pickup, at my convenience and on their nickel. The machine was picked-up this past Wednesday. So, for know, I’m in a holding pattern awaiting feedback from Sandbox. Will let you know the outcome once I hear back from Sandbox. Cheers. A.