Sony Xperia Z is Sony’s latest flagship device. It is one of the best devices out there and it has done quite admirably in the market. Although this device has some great features, many users were not satisfied with the low sound quality, or at least volume of the device’s external speaker – an issue that may stem from the speaker’s water resistance or its small size.
Nonetheless, this problem has been addressed by XDA Senior Member ZeroInfinity. He has managed to increase both the internal and external sound volume with the Extra Volume Boost mod. This mod is available for the stock Sony ROM as well as any AOSP based ROM. Follow the instructions below to install it on the Sony Xperia Z.