I have it as well, and like the other poster mine faded at around my early 20's. Music had vibrant color and texture, and for me quite a few words did. Numbers, 1-9 all had their own colors and I still "see" those, or at least I strongly associate them with the colors I saw, like "three" felt green, five was orange and seven was red. Up until I was 18 I didn't know it was rare, I was describing a song to my girlfriend and she'd heard of Synesthesia. I miss it very much.