Try turning "Advanced Calling" ON (or OFF if already on) & see if that helps.
If the phone is anything like the previous Droid Turbo, there isn't much hope. I took the Turbo back due to low volume/horrible call quality issues. Only using the speakerphone helped.
The only fairly recent Motorola phone I found to have good sound quality & an abundance of earpiece volume is the 2013 Droid Maxx. The only problem is they don't make it any more
No current smartphones sound as good or loud as my ancient LG flip phone that has survived 2 trips to the washing machine
Making sure your friends can hear you is a priority. We encourage you to power your device off and then back on. If you have any cases on your device please remove them and test again. Also, if you have any screen protectors we encourage you to make sure none are covering the microphone.
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