If it was pulling too much current, it should trip the breaker. If it is the adapter that is burning up, I would agree with another poster that there is a fault in the adapter. There is evidently a high resistance connection (resistance produces heat) in that connector. The dogbone or adapter is either defective or not making adequate contact plug/outlet. Be sure that the prongs are clean. Be sure that the outlets are gripping the plugs securely. A sensitive ohmmeter should be able to spot the high resistance connection for you, by the way.
