i remember once listening to a few tunes on the hifi with my headphones plugged in, i whacked the volume and bass up, because my headphones didn't have enough low end rumble. when i had done, i unplugged my headphones and turned the hifi off.

Now no problems so far, except i had my hifi set to wake me up in the morning, i'd forgot i'd turned the volume and bass up, so at 9am, the whole house was shaking with techno, boy did i jump up out of bed