My last name, Houle, doesn't get misspelled very often, but a lot of people mispronounce it. A lot of people pronounce it like 'Howl,' some say 'Hooley,' some say 'Howley.' Usually the only people who pronounce it correctly ('Hool') are the ones with French names, too.
I would actually assume it was pronounced "ool", as "h" is usually silent in French at the start of a word. (There was also a hockey player in the 1960s and 70s named Rejean Houle, so the name was already familiar to me.)
I have never personally met a Randolph though there was a Australian writer called Randolph Stow. Randolph is certainly rarer than Randall.
In Australia, if Miranda was shortened it would likely be shortened to Mandi because of the slang meaning of 'randy'.
I know a Randy - I think it's short for Randolph, but I'm not 100% sure. He certainly appears to live up to it.
There are people in my family tree with the surname Hough. I was wondering how people here would pronounce it?
I pronounced it Huff, for
this reason.
That's the same reason I know how to pronounce it.

Now, if I heard the name and was asked to spell it, I might very well spell it "Huff", but I've been friends with the science fiction/fantasy author
Tanya Huff since I was in high school, and she worked in a bookstore I frequented. (I'm actually a character in one of her books,
The Better Part Of Valor. She made me a fighter pilot, which is ironic, since I don't even have a driver's license.

)
As for my name, most people - at least those who are fluent in English - seem to be able to spell the first one, though I'm occasionally asked if it's short for "Lancelot". (No, it isn't. It's just Lance. And my middle name is really Arthur. You'd think my parents had a Camelot fixation, but using the name Arthur is actually a family tradition on my father's side.)
I've long given up on expecting people to be able to spell my last name, though - it's only six letters, and it's spelled exactly how it sounds, but it's uncommon enough that most people have never encountered it. So generally I just immediately spell it when I'm asked for it.
There's probably only one moderately well-known person with the name - and he's an ornithologist, so "well-known" is a relative term. (It's English, but it originated from a Greek word meaning "sorceress". Maybe I'm descended from Morgan LeFay and don't know it.)