Disadvantages to Synesthesia

From: Listverse- 10 Disadvantages of Synesthesia
Something I learned from this blog is that people with sound-color synesthesia are more drawn to people with "pretty voices" because they associate the sounds of their voices with colors that can evoke emotions in the synesthetes that make the person appear friendlier than a person with a not so pretty voice that evokes colors that make the synesthete feel uncomfortable or unhappy.
What a "pretty voice" is defined as must be very subjective depending on what sounds the synesthete associates with what colors and what colors rub the synesthete the right or wrong way. I've read that synesthetes don't experience things the same way even if they do have the same type of synesthesia. For example, a sound-color synesthete could see lime green when they hear a sharp sound while another sound-color could see firetruck red when they hear the same exact sound. So if you ever meet a sound-color synesthete who doesn't seem to like you much and you don't know why, it could just be the sound of your voice. But don't worry, there is probably another sound-color synesthete out there who wouldn't mind being friends with you.

Another thing I hadn't realized is how synesthetes' condition hampers their ability to do other things such as math. People with OLP synesthesia (definition from wikipedia:a form of synesthesia in which ordered sequences, such as ordinal numbers, days, months and letters are associated with personalities) might have trouble adding a "mean number" to a "nice number". Likewise, Someone with grapheme-color synesthesia and experience in color theory might have trouble understanding that 2+5=7 because 2= pink, 5=light blue and 7= red and pink+light blue doesn't equal red.