I am wondering why nói is added at the end of the sentence?
It means something like "speak" so maybe adding it means "Sorry I do not hear you speak" which is not wrong, but NOT what Duolingo is asking to translate :\
Maybe it's a connotation thing? Like in English it's assumed you didn't hear someone speak unless otherwise stated. Maybe in Vietnamese the default is something else.
Similar to "I don't hear you speak.".
"thấy" is not strictly necessary. One can say:
"Tôi không nghe bạn nói."
Why is "thấy" added after "nghe"?
I dont understand the use of "thấy" at the end, and yes I did read the lesson notes.
Why is thấy used here - what does it accomplish?
How would the sentence meaning change if thấy wasn't used?
I think I would have added ''rõ" (clearly) at the end of the sentence in real life situations
Is placing "alright" at the end of a sentence not used in practice?
Xin lỗi, tôi không nghe bạn được
In this usage, được would mean "can" as in "sorry, I cannot hear you".
While grammatically correct I don't think people ever say "I don't hear you" in English. "I can't hear you" is much more common.