I kinda agree with the OP. The Clip+ is a bit too lively when compared to most players. In the past few days I'm listening to an ipod touch more than before and, since I'm used to the sound of C+, it sounds boring and mushy (the ipod that is). It's because I got used to the sound of the C+.
Either way it's not a fault just different style.
Edit: Also, depending on the head/earphones, most other players tend to extraggarate the lower mids due to their higher output impedance. This is most likely the main reason why the C+ sounds more harsh with most earphones.