something in my office has started buzzing/rattling/vibrating. i think it's in the ceiling, or possibly the wall. i thought it was my speakers spazzing out, but i turned them off and the sound continued. i thought then that it might be the new light bulbs, or something involving the light fixture as a result of the work they were doing the other day, but the sound persists even with everything turned off. it's really starting to freak me out.