Narrated Abu Hurayrah (RA): The imam is responsible and the mu'adhdhin is trusted.

اَللَّهُمَّ أَرْشِدِ الْأَئِمَّةَ وَاغْفِرْ لِلْمُؤَذِّنِيْنَ

Allaahumma arshidil a-immata wagfir lilmua-ddhinin

O Allah, guide the imams and forgive the mu'adhdhins.

Reference: Sahih (Albani). Abu Dawud: 517