pronunciation of 人 - regional or gender differences?
The two speakers sounded like they were both saying 人 with a [ ɻ ]. One's voice was higher pitched and the recording conditions were different though. In practice, you're going to run into pronunciations way more divergent than those. All the people I've met from 青田 say it with a [z] (note: not a pinyin "z"). Also, I've run into a few people who use an [l]!

My advice: Listen to a lot of people, chat with a lot of people. You'll pick up on which distinctions are important, which aren't, and which are regional.