Switch primary and secondary mic @ rooted android 7.1

[Tobias Brohl]

I want my secondary mic to be used for as primary mic , I found out that this needs to be done in the mixer_paths.xml, but I don´t know what to change exactly on my Bq Aquaris U lite. I tried some stuff out but they didn´t change anything.
Link to my mixer_paths.xml @ GDrive: https://drive.google.com/open?id=0B-6EvcKF4HvIU2pzYmszdnRfZlk