Ok, Vernon, so basically, if I understand your response, I turned it off and on again too fast? Thanks for the explanation.
Yes, that is one possible way to invoke the problem.
PS3 and many control systems are state machines. By state machine, you understand how a E-unit basically cycles, forward, neutral, reverse, an advanced sound system powers up with startup sounds, then transitions to moving sounds, then last, transitions to shutdown sounds if so equipped.
Especially true in modern engines, these control systems have more than one processor. Typically one controlling the movement and lights, one controlling sounds- and the 2 talking to each other over a protocol. But because they are separate things, and this protocol of control is limited, it's entirely possible to get one side of the machine in one state, and the other side of the machine in another state and now we have this mismatch. Sometimes this can be caused by sudden power loss, other times just the right communications glitch, but again ultimately you get the system into a state of mismatch.
The way to fix that is power down completely. This forces everything all the way completely off. Now when you re-apply power, the system is forced to boot up into a known baseline state. It's now ready, everything matches normally.
This is why a reset to defaults would do nothing to solve the problem. That reset changes settings- not the state machine state.
Again, the truth is, this is not just an MTH PS3 problem, it can happen to other systems as well that use more than one processor.
I know the "try turning it off and on again" is often a joke and quoted in computer or technology aspects, but it solidly applies to our trains as well.