when I got my first V3, just after release, I found the sound recording to be good
My second V3, a few years later, wasn't as good, sounded muffled
The second V3 also had the rattly buttons issue (another thread here) and when I opened it I also found the microphone to be in a different, more embedded location
I moved the microphone closer to the outer edge, near to some vent holes, and it's been fine since