Radio sound poor quality

Davectr

I recently bought a 2010 370z roadster (Bose, sat nav) and when listening to the radio it sounds like listening to a mobile phone (no bass at all and very tinny) even adjusting the sound settings doesn't help. But, when listening to a Cd or the music box the sound is quite good and full of bass. I've searched the forums but can't find an answer, and don't understand why it should be like this? It's spoiling the overall enjoyment of the car as I usually listen to the radio most of the time, but I'm finding that it sounds so bad I have to listen to CD's. any advice greatfully received