I have a similar thing but with music/sounds - I do a lot of work (albeit non-professional) with audio and I when I hear things I tend to visualize a sort of wa

I have a similar thing but with music/sounds - I do a lot of work (albeit non-professional) with audio and I when I hear things I tend to visualize a sort of waveform or overall shape/envelope to the sound. There are other visual aspects to certain types sounds that accentuate it. It seems like a very slight, learned synesthesia.