The condition of hearing a persistent or intermittent noise, when no external cause for the noise exists, is called "Tinnitus".
Tinnitus is the point at which you can hear sounds inside your head that are made by your listening ability framework, not your condition. It could be a ringing, beating or murmuring. It is more noticeable in calm territories or at evening time. It as a rule has no specific reason however can be dealt with.