Getting ready to add an amp and sub to the factory unit on a 2017 sport model. Am I going to run into problems just tapping into the back speakers with the ANC. If so, how can I get rid of it and keep Bluetooth?

 

You will want a line output converter that provides bass restoration because the rear speaker signals have a high pass filter on them within the head unit. This means that there is very little bass going to those speakers.

The ANC mic wires are separate from the bluetooth mic wires. Simply cut the ANC mic wires or remove the external ANC module altogether.