When you first get this pull the plastic ear piece off there was a small dust cover on mine that was muffling some of the sound super loud now
Very easy on the EAR...
8 to 10 hrs easy...
Also accidently dropped mine in a sink of water (45 seconds) the unit stopped working.
I put the earpiece in a small plastic sandwich bag with rice for 24 hrs. then charged it.
Thankfully: All functions working again....
I complained originally about not receiving the advertised bandwidth.I found out it doesn't matter.I recently turned to an experience friend who uses these devices.After her examination ,she was was awed by this device.My phone wasn't set properly.She tinkered and bingo it was working terrifically.She pointed out the ear piece adjustment ,which can turn to fit my big ears without falling off.She had me tilt my head right and left and the ear piece stayed on.Then she called my phone .Since we were indoors ,the reception was clear and my voice carried over the short mic piece without undo distortion.Then my fiend went outdoors and called me.Again everything worked out.Tne final test came when I rode on a downtown NYC bus-still wearing the ear piece I received a call from her-almost 2 miles into my ride.Though there was some traffic and bus noise my friends voice came through.One truth,I'm a clutz when fitting this ear piece to my own ears.