Couple months back I bought a new Sony Headunit MEX-BT3700U for its Bluetooth and iPod (usb) capability. All functions work fine except when I'm using bluetooth with my cell phone the person on the other end can barely hear me, they hear static. This only happens when I press on the accelerator while using bluetooth. If I'm stopped or let off the accelerator while talking with the bluetooth the person on the other end hears me fine. I can hear the person fine on my end whether I'm on the accelerator or not. I'm wondering if alternator is causing some kind of interference in the bluetooth mic.
I've had sony headunits prior to this and the wiring harness is the same so I unplugged the old one and plugged this one in.
Any ideas why this may be happening? Thx!