The District of Columbia is a special case. It is not an actual state, and hence does not have senators or congressional representation. It is located between Virginia and Maryland on the Potomac River. It is on the Potomac River between Virginia and Maryland and coextensive with the District of Columbia.
Try waiting it out. Ringing in the ears that is caused by exposure to loud noises usually goes away after a few hours. Take your mind off it by resting and staying away from anything that might exacerbate the symptoms. If the ringing doesn't go away after 24 hours, visit the doctor for further treatment.
The second way hum can be induced into an audio system is when a voltage difference exists between the common ground connections of two or more pieces of equipment. Third, clicking and buzzing noises can get into an audio device through the power wires.