Kind of hard to hear the teacher. It may be better on a higher recording quality or mic sensitivity.

The headphone mics are amazing. It makes the teacher sound like they are talking to you from inside the pen... Only problem is it takes up a ton of memory. But good for big lecture halls. If the playback sound is too low, using the headphones are fine for playback. I have my pen 1 week. I never expected it to work so well, and I usually sit in the back of class or lecture hall. And the sound pick up is fine. Several folks put their old fashion recorders on the teachers desk... This is not needed with the Pulse.

Loved it. Like most Americans, I love Calculus, though, so I might sound a little biased...

Sound is too low. Can't really hear the teacher.

is it just me or there's no sound?

Thanks for this! I have yet to receive mine so I'm interested to see reviews like yours - can't wait to hear audio with a higher setting ^_^