I have done some changes in Mixer_Path.xml which helped to increase volumes.
Hope that helps Z1C owners who need only some boost in sounds rather than third party custom sound mods.
Device must be on stock KK rooted and this also may work on XZ1
PLACE THE MIXER_PATHS.XML FILE IN SYSTEM/ETC DIRECTORY WITH 0644(RW-R--R--) PERMISSIONS AND REBOOT
Hit Thanks if you liked it