sound quality is good once charge 4 hrs play music and 5hrs for movies first 100 to 50power discharge take 3hrsapprox but next 50 to 20 take 1hr in 20 battery indicates battery lowbelow 20 we cannot use because it will going to off automatically so battery 20 is like 0i bought it and face these problems so again replaced by new one but again these problems comes then only i realised the product manaufactured like thatafter that i am contact mivi customer support and se