Terrible noise!

[misterpete]

Sitting downstairs today when we heard the most terrible noise from upstairs, it sounded like someone dragging chains across my roof. Went up to investigate to find my Gold Phantoms making the most awful deafening noise, I quickly turned off all the power but I am nervous about turning them back on again. Even if they come back on OK , I dare not leave them powered in case they do it gain in the middle of the night.
Anyone else experience anything like this?