It is unclear whether this system is a common AA trait; the Chadic examples, for instance, show signs of originally deriving from affixes, which could explain the origins of the alterations in other languages as well.
ɪɾ ɪz ʌŋklˈɪɹ wˈɛðɚ ðɪs sˈɪstəm ɪz ɐ kˈɑːmən ˌeɪˈeɪ tɹˈeɪt; ðə tʃˈædɪk ɛɡzˈæmpəlz, fɔːɹ ˈɪnstəns, ʃˈoʊ sˈaɪnz ʌv ɚɹˈɪdʒɪnəli dᵻɹˈaɪvɪŋ fɹʌm ɐfˈɪksᵻz, wˌɪtʃ kʊd ɛksplˈeɪn ðɪ ˈɔːɹɪdʒˌɪnz ʌvðɪ ˌɔltɚɹˈeɪʃənz ɪn ˈʌðɚ lˈæŋɡwɪdʒᵻz æz wˈɛl.