Are you using the included 110V adapter or are you running off a 12V DC source? I had a customer with a similar issue. His charger was getting very hot using 110V so he started to use a 12VDC for input instead. The problem continued but we found out why. His 110V adapter was putting out almost 20VDC (under load). This caused the voltage regulator to overheat. When he decided to use a 12Vdc source he chose his 12V car battery charger. Not good. Those chargers don't have a regulated output (not needed when charging 12V car batteries). So his Revo charger was again over heating. He now uses a small regulated 12V power supply and has bought a new 110V adapter. We're still not sure what dammage/abuse/defect caused his adapter to pump out such high voltage but it was the cause of the charger getting hot.
Hope this helps.
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