Originally Posted by doogald
Settings / sounds / volume. There is a volume slider for notification volume there, which is different from ringer volume.
My Moto X only has a single slider labelled "Ringtone & notifications". I've also noticed that I never seem to hear text notification sounds. I'll try the A-Volume widget (https://play.google.com/store/apps/details?id=com.svk.avolume
), since it has good reviews (and a lot of dev replies).