Good day everyone, I am new to this site & I hope someone can help. I recently purchased an Avant head unit & wiring to replace the outdated factory head unit. Installed & connected up & everything works except sound, I have vehicle stats, wifi, internet, GPS, steering wheel controls, just no sound from radio or media files. Avant help are trying but some of the information I get conflicts & the install info does not show the connections on the rear of the unit or in the back of the car.