You can do 1 thing that I have discovered first of all for the audio problem install sound about software and Player Pro with DSP pack of player pro. The sound about software and Player Pro with DSP pack will take care of your sound in balance problem for the audio that are in your phone and SD card. For the online videos disable the inbuilt Sony music Android setting and music FX after that install equlizer plus from the Google Play Store. Set the equaliser at the intelligent EQ and make surround option to the full also make balance button on this will resolve your online video and other live stream sound imbalance problem. Remember PlayerPro and DSP pack if for in built audio track that are on SD card and internal memory and the disable part is for online videos and other live stream all the best.