Camera E27 suddenly stop making sounds

\n\nMy camera stop making alarm sounds, no ding dong sounds, Is there anybody who can help me??  V starcam Support can not fix this problem. I already reset the camera twice, uninstalled the app twice, sounds settings in the app done, what else?  please help.  

Dear Sir/Madam，
Do priciate for your promptly feedback , I have knowed about your E27 camera problem,  dingdong sounds from camera microphone,
you must add door sensor to E27, and open door sensor sound in APP too.  I give you operation videos, can you tell me your email address?
I will send it to you via email.