Again, here is the problem with using the wrong adapter even if it appears to "work".
#1 you are putting the wrong voltage in higher than expected, and thus the voltage regulator inside is converting that energy into heat- extra heat and could burn out.
#2 Even though it appears to work, again, that is not the correct adapter and likely is not properly grounded internally. This affects the Legacy signal to the trains, but again requires the correct adapter or an alternate that has been verified or modified to have correct grounding.