http://4pda.ru/forum/index.php?showtopic=541742&st=14520#entry40526116
all simple? needed sounds in apk /system/priv-app/MiuiSystemUI.apk
MiuiSystemUI.apk/uzip://res/raw/
charging.ogg
disconnect.ogg
i open apk by MC , you can use 7Zip or WinRAR
i try change sounds to not so annoying, or just...