M072 (S160) Android Head Unit Install/Info

[xtech]

Well, both mics work for bluetooth calls. The difference lies in the fact that the external mic doesn't "communicate" with android in the sense you cannot use the google voice assistant for voice controls (unless you do the mods of my previous posts). The internal mic allows that. So unless you face serious problems with the internal mic (like low voice volume, etc), i see no reason to use the external mic as you will lose functionality.

This what i can conclude from reading the roadnav forums, but my unit hasn't yet arrived. If someone can confirm this, it would be great.