Audio volume has fallen on my 2013 Moto X, how can I fix it?

[dlemper]

Audio volume has fallen on my 2013 Moto X

The past few days sound output has fallen. First noted when I slept through
the alarm. I missed several calls. Now ring is barely audible : detect a call
primarily by vibration.
This is a carrier-unlocked phone obtained through Amazon in Dec 2014.
I'm running it through the AT&T on Android 4.4.4 . Never been updated, but
that's another gripe.
All volume settings at maximum, including those under 'Settings' and with the
side buttons. Changing ringtone didn't help.
Everything else seems to work. Most recent App I put on it was LastPass
less than a week ago. Has never been damaged.
Any help appreciated.

 

[dlemper]

My son examined this phone and says my hearing is going.
He believes the phone is fine, other than lacking an upgrade
to Lollipop. dlemper