Are you in a 16 or 17? Audio in the 17 is notably better, and has been pretty satisfying in my experience. You will also notice a difference when on Bluetooth or plugged in via USB
I was playing with the radio on my new-to-me early 17 model and it does seem the bass is a bit weak. But overall it seems to have very good sound. Usually I wouldn't know the difference since I'm 66 and have the usual hearing loss - but usually bass does get through pretty well. I haven't seen any mention of an option in any literature I've read.