I have female ("eunuchoid") skeletal proportions and visually, I look a lot like someone with Klinefelters. I had quite a lot of tests done last year including a pituitary MRI, and I have congenital hypothalamic secondary hypogonadism. My testicular function appears to be completely fine, with the problem just being that my brain isn't sending out enough of the signal (LH) that tells my testicles to produce testosterone. In March this year they started me on testosterone replacement, and from what's happened to me since then, it's clear I'm not androgen insensitive in any way, the thing that's made me androgynous looking has just been low testosterone the whole time.
In my case there's so many similarities with what seems to commonly happen with prenatal DES exposure (hypogonadism, eunuchoidism, feminised personality, behaviour and gender identity), that I'm pretty sure the cause is being prenatally exposed to synthetic female hormones. The conventional causes of intersex all tend to act throughout that person's prenatal development, whereas what appears to have happened to me is completely male development for most of the pregnancy, but with a period of completely female development partway through. Again that ties in with exposure to testosterone blocking hormones/chemicals as the cause.
I was born with a hydrocele, and when I was about 10, a loop of my intestine dropped through the gap where the hydrocele was, creating an inguinal hernia. Hydroceles and childhood inguinal hernias seem to be quite common among male assigned intersex people.