Alcatel 4s sound not working in viber

[Llorance]

Hello, I bought this phone (I live in Ukraine). Everything was fine until I installed the Viber. Viber was established and activated. I'm calling a friend, I can not hear a call, he picks up the phone and I can not hear him and he can not hear me. Do you guys know how to solve this problem? I bought myself this phone, I could not even imagine that it was possible:angry: ... I really need this program. Help!:smile: