Some verb morphology features of Tadaksahak, or Berber or Songhay, this is the question

Having been described as "langue mixte" (Lacroix 1971), this language presents features of Songhay and Berber languages. The observations discussed in this paper deal with the way voice changes are handled. In particular, it shows how the causative is formed. The causative morpheme S(V)- is of Berber origin and prefixed to the verb root as in Berber languages, whereas Songhay suffixes the causative morpheme that is of a very different form (-andi). But only verb roots that are also etymologically from Berber can take the morpheme in Tadaksahak. All roots that are cognates with Songhay are replaced with a Berber root with the same meaning, when causativized, changed to passive voice, or made reflexive or reciprocal.

An appendix to the paper lists examples of both intransitive and transitive verbs using suppletion of the root when changed to causative and passive voice.