if you get in & don't turn the engine on, do you hear a humming noise?
like the cd is trying to load?
The cd players are known to be cheap junk. same issue here, it makes the loading sound.
i pulled my radio fuse 'cause the cd player kept draining my battery.
be careful you don't get the same thing!
it has NOTHING to do with your shifter, or anything else.
it is just the cd player unit.
i have a 2006, & I'm having the same issue as you.
its a common thing with these CD players.
maybe try a junk yard, or salvage place for a replacement.
you would have to replace both the player & radio, cause I believe they are 1 unit.