What should a man do if he feels that his wife is cheating on him and calling out another name other than his?

It is impermissible to accuse one's wife or anyone else of unchastity without clear proof, for that is among the major sins and incurs the punishment for the false accuser. If a man's accusation of his wife is based merely on suspicions or her mentioning another name, then it is not permissible. The default state for a Muslim is innocence, and whoever has accused unjustly must repent and expel those satanic whispers. However, if he actually sees something suspicious, and not just mere suspicions, then he must ascertain the matter and not remain silent. And it is incumbent upon the man to fulfill his duty of guardianship over his wife, to close the doors to temptation, and to establish God's limits in his home.