Brief Answer:
it is called tinnitus

Detailed Answer:
HI, thanks for using healthcare magic

This would be tinnitus.

Tinnitus refers to the hearing of sounds when there are no external sound present.

Some persons may hear buzzing, ringing, roaring etc

There are different causes such as: (1)age related hearing loss
(2)side effect of medication
(3)infection
(4)trauma
(5)wax in the ear
(6)meniere's disease
(7)prolonged exposure to loud noises

You can consider assessment by your doctor to determine if there is reversible cause like infection or excess wax.
If one of these is present and treated then the tinnitus should resolve.

A hearing assessment by an ENT doctor would also help. If the tinnitus is related to some small hearing loss then a hearing aid may help.

At present there is no cure for tinnitus unless due to a reversible cause.

I hope this helps, feel free to ask any other questions

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