Thanks for you input, after reading a summary of your sensations, and I interpret what you said to mean physical sensation due to sound when you said,
"I startle easily and when I get startled, I do get a very intense pin-prick/"pelted with sand or tiny pebbles" feeling from the general direction of whatever startled me. The intensity of the physical feeling is directly proportional to how badly I'm startled."
is it the same sensation "physically" as it would be if you were actually pelted with sand, or in your "minds eye" so to speak.
You also should review Fuzzyfelt's thread below:
Do you get musical chills ?
and listen and then watch some of the videos, and report what you feel, sense.
It would be an interesting experience for you, and I am sure we may discover some new things especially since you have multiple forms of synesthesia.
I guessed "google" was you discovery method, that must mean our thread is fairly highly ranked. I hope you stay awhile and browse other forums, their is a ton of good information to be had here. Be sure to use the advanced search feature and type in members ID's who post interesting stuff. Chances are you will find more interesting topics.