I'm finding MANY limitations with the Droid Turbo 2 phone regarding volume AND sleep mode.
In general, you can NOT adjust the ringer volume AND the notification volume separately. That is what the Motorola tech told me after she told me that I was holding a very advance phone compared to the old phone which DID let you adjust volume separately. So if you adjust the sound of your phone call then your ringer will go up, too. And I had to delete my Do Not Disturb App because it was interfering with the phone's Interruptions setting which they could not fully or logically explain.
To adjust sound, it's best to go under the Sound and Notifications in your Setup because the side volume is linked to whatever is in the complicated MESS of epic fail that is within the Setup of the crappy phone that I regret purchasing!
And if this response seems confusing, try talking to Motorola about it...it gets worse!
The combined ringer volume is an Android OS for the Lollipop version. I'm not positive, but I think it should be corrected whenever the phone gets Marshmallow 6.0 as I think Google split it again. If you had a fairly old phone previously with an older OS version where the ringer volume was separated, the combined volume wasn't well received for many when Google changed the Android OS in Lollipop (or was it Jelly Bean?).
I'm most definitely NOT a VZW employee. If a post answered your question, please mark it as the answer.