What’s the ruling on someone who frequently utters kufr unintentionally?

If a person frequently utters words of kufr unintentionally, for example when trying to pray (the person is accustomed to unintentional pronunciation errors: he fails to pronounce the letter mīm when he tries to recite the basmala, sometimes says yawmi -d-tin or place of yawmi -d-din or na`bu instead of na`budu etc. when trying to recite sura al-fatiha…)

is he considered a kafir out of the fold of Islam? Should he repeat the shahada (after each unintentional utterance of kufr) ?