Annoying buzz when using aux jack
 

Greetings. I recently picked up a cosmic blue MS3. Love the car! However, when I hook my Sirius up using the aux jack....I am getting an annoying buzzing sound. Any ideas on what would cause this/how I can get rid of it? Thanks so much!!

check the grounding

mazda insufficiently grounded/shielded the aux port. Get a 3.5mm-3.5mm ground loop isolator and plug that inline and your problems will be gone.

Look HERE