When i first got these and paired them to my phone they seemed pretty good,not great as i was aware you need to burn in most headphones etc. Then the 1more app said there was an update, this is where my problems began. I had downloaded 1more assistant app and started the burn in process when it said i needed to upgrade the firmware, so i upgraded the firmware or so i thought i had, turns out i had only upgraded one because i wasnt using the latest 1more music app. so now for some reason only one of my earbuds was working and after going to the 1more website I discovered i needed to use the 1more music app to upgrade them and that they should have been upgraded individually and not as a pair as i thought. The major problem now was that i couldnt get the ear buds to pair to each other again, i managed to get them both into pairing mode but that didnt help, i even used the reset process of holding the buttons down for 5 seconds in the charger unit until the lights turn a purple colour, your then supposed to take them out and press the buttons 4 times to get them to reset and go back into pairing mode... this did not happen, I tried for almost a day until somehow they just suddenly paired after i put them back in the charger and took them out again. I have never had these sort of problems before with any electronics and i like to think im a little tech savvy but these have been a challenge. I understand part of my problems was from user error and i should have gone to the website first and checked how to upgrade them but we usually expect apps to do this for us and lead us in the right direction, using the 1more assistant app was my first mistake i guess. So my advice to anyone buying these is make sure you use the correct 1more music app and upgrade them individually, then download the other 1more app and begin the burn in to get the maximum sound quality from your ear buds. I'll update this review once the burn in process has finished, which is roughly a week judging from the time on the 1more app.