Hey all. I just picked up a Boxster S last week and decided to upgrade the radio to something that did hands free and charged my phone.

I picked up a Sony media player head unit (DSX-a415bt), which came with a Crutchfield wiring harness. I installed it and it works great for blue tooth/radio/usb.. but when trying to make a phone call it goes silent. According to the Sony manual that “the front speakers aren’t connected” as it sends a signal to the front speakers for phone calls.

Everything is connected and works, except phone calls. Out of trial and error, I reversed the RCA plus on the back of the deck, and the phone calls started working, but all the music only played bass.

I suspect this has something to do with factory amp? Crutchfield didn’t seem to have any answers, anyone run into this?

thanks!