Take care! The accent on σου does not exist, even heard here. It shouldn't!
If we put an accent on σου when we speak, σου is not the usual possessive pronoun, but an object. This is not the case of course.
Ο πρόεδρός μας αρρώστησε (ο δικός μας πρόεδρος αρρώστησε)= Our president got sick. (possessive μας)
Ο πρόεδρος μας αρρώστησε (ο πρόεδρος αρρώστησε εμάς)= Our president made us sick. (object μας)
Notice: If there are two μου (one possessive and one object) in series, the second takes an accent. But I don't want to make it more complicated, skip it, it is ambiguous for linguists too.
Some explanation about why happened it in the above phrase:
The problem comes from the incapability of Duolingo to put two accents on άλογο, as it is usual: Το άλογό μου. Since NO word in Greek cannot be accented more than the 3rd syllable from the end, and the possessive is pronounced as one word with the άλογο, άλογοσου, a second accent is put on άλογο, that is άλογό σου. Since Duolingo cannot do it, as the TTS recording is based on words as units and not on phrases, as a whole, Duolingo puts a second accent on σου when heard. Completely wrong!
I remember I reported some bad recordings when I finished the tree some months ago, but we are in the official version now and Duolingo didn't corrected them yet. Especially in stress in words or even phrases, question marks that do not exist, phrases said with a special stress in voice, that gives a color the phrase etc. I think the Greek team has nothing to do with the wrong recordings. But please, Greek team, just delete the wrong recordings if you can. as much it is possible.
Horses lick salt for trace elements which they require for nutrition.