Why do I hear an abnormal sound from my Nokia Asha 503 phone?

[Windows Central Question]

why i hear abnormal sound from my nokia asha 503 phone ?

sound is a "beep" sound like an error sound in other nokia phones or like a battery draining out sound.
no specific time gap.sort of irregular .....please help

 

[Srisai Ganesh]

I think likewise old mobiles our Asha sends beam of signals to restore operator signal at week areas.