Not quite pronounced the same. It's a difference between lilted 'r's and rolling 'r's.
If the word starts with an 'r' or there is a double 'rr', then that 'r' should be rolled (relax your tongue against the roof of your mouth and blow; you should sound like a purring cat or motorboat). https://studyspanish.com/pronunciation/listen-and-repeat/letter_rr
Otherwise, if it's just a single 'r' in the middle or at the end of the word, then you should lilt it (flick your tongue against the roof of your mouth like you're almost about to pronounce the letter 'l' instead). https://studyspanish.com/pronunciation/listen-and-repeat/letter_r
Same for me. Voice recognition software refuses to recogize"un" and "centuron" and the default options pop- up windows don't contain it. There full of spell and gramatical errors. This expends more of my time than if I had just typed in the answer, instesd of using this "time saving" technique.
the one 'R' in "caro" should be lilted (have your toungue almost flap against your pallete like your about to pronounce the letter L), https://studyspanish.com/pronunciation/listen-and-repeat/letter_r
while the double 'RR' in "carro" should be rolled (this sound's a little harder to make, but might remind you of a purring cat or motorboat engine) https://studyspanish.com/pronunciation/listen-and-repeat/letter_rr
That said, it still something you have to have a good ear for; I still have trouble differentiating the two sounds, but that's probably because I haven't been practicing in a while.