I found a problem with the translation/pinyin for characters that can have different pronunciations.
Example: Short Story 11
一个公寓很便宜
便宜 Can have two meanings Pian Yi (cheap) or Bian Yi (convenient).
The text uses Bian Yi, but actually meant is Pian Yi (which gets clear later because of opposite is expensive = 贵)
The AI audio is correct and uses Pian Yi.
Will add more as I find them. Will keep writing here.
1a: 着 - wrong pinyin zhao - correct is zhe (AI audio is correct)
11: 便 - wrong pinyin bian - correct is pian (AI audio is correct)
12: 还- wrong pinyin huan - correct is hai (AI audio is correct)
I suggest you have all Mandarin mini-stories checked.