Darkroomsource: "There is a theory that makes complete sense, but does not answer all the questions. The theory is of an undetected fire in the wiring in the cockpit area. If the fire melted wires in "the right order..."
Sorry Darkroomsource, there IS a theory that "makes sense", i.e. fits all the known facts, and it is NOT fire. It is "human intervention", which is now the official explanation.
For example, at 1 hr 43 minutes into the flight, the Satcom mysteriously logs on, 3 minutes after the last primary radar contact. The link is re-established after being lost at about the same time as the transponder and comms, 25 minutes into the flight. Did the wires unmelt more than an hour later, after the aircraft makes a bunch of left and right turns, flying past Penang, the pilot's home? That's like picking up a copy of Shakespeare's Romeo and Juliet and saying "This makes complete sense. It was randomly typed by monkeys."