What should a student do to avoid disturbing his Christian neighbors who play the guitar, despite his repeated requests for them to stop, given his fear of a quarrel breaking out?

Denouncing evil has stages, beginning with the hand, then the tongue, then the heart. One must consider one's capability, the outcomes, and balance between benefits and harms. Therefore, it is not permissible to denounce evil in a way that leads to greater harms. If neighbors play loud music, one can speak with them in an appropriate manner, and seek help from wise people or officials. Whoever hears music unintentionally and dislikes it in their heart bears no sin.