Cd quality. The quality of the cd music on my Bose is consistently inferior to the

Question

The quality of  the cd music  on my Bose is consistently inferior to the quality of the music on the FM band. It seems to lack upper frequency response.It lacks the presence and fullness of the FM music.
I bought this system perhaps five or six years ago. I am wondering
if there is some sort of maintenance I should be doing to improve the
reproduction...something similar to a head cleaner I use on my camcorder?