My current lover is actually very interested in this; When we first started dating, after a good shag she held my balls in her hand, fiddled around a bit, squeezed lightly and said, "It sounds really bad, but everytime I hold a man's balls in my hand, I want to squeeze them till they rupture....I just want to see how it would feel." Apparently she has said this to many a male lover, and was even once kicked out of bed for saying it...I revealed my "fetish" to her shortly thereafter, and she now knows that it takes a lot more to break 'em than she imagined, though I'm sure she could manage if she really tried!
That's a good idea; I wonder what the proper foley technique for popping testicles is..maybe micing up grapes and smooshing them in a bag? For those who don't know, foley is the art of making sound effects with physical objecct, like punching a watermelon for someone getting clocked in the head, etc.. a common way of generating sound effects for film.
Your focus on the audio aspect of our kink is very interesting to me....Have you ever wondered why you have that particular focus?
One my most common fantasies that is played out in the "blue movie theater of my mind" in manifold permutations is that of a mistaken identity, where a woman mistakes me for a ****** or sex offender (I just happen to look exactly like him, ha), or someone who grabbed their ass at a club,and I am subsequently *********, tortured, kicked in the balls, etc....
Try that one on for a story perhaps.