That's interesting, our printer is in a pretty well regulated room. I need to confirm this but isn't the build chamber supposed to be regulated? I suppose it can heat the chamber but not cool it. When we received our printer in 2014 the ribbon cable between boards had worked loose and needed to be reconnected. By unplugging and reconnecting the connector it solved a bunch of issues for us. I'd let MakerBot know about the temperature issue, and how severely it affects your builds. I have access to a data logger I can connect a temperature probe to, you've got me curious about build chamber temperature variations.