I use Xperia M(Model number C1904/Android version 4.3) to record music from my digital piano(Privia PX-160) using an auxiliary cable.The recordings have a very faint voice with a lot of buzzing noise.I have tried many voice recording apps and changed many cables but I'm unable to get rid off the noise. Can anyone suggest me any methods for troubleshooting?
you have probably got a ground loop going between the keyboard and the computer. Try the following:
a) disconnect the power-supply from the computer and use batteries only. b) make sure you have adequate gain coming from the digital piano and you can see a reasonable level begin recorded.
You will not get good recordings using anything other than an interface and DAW. Buy a small sound card for a few hundred bucks and a freeware DAW like ableton.