I had this problem, using my Samsung mobile phone (S10+). The volume on my phone was all the way up, yet outside when I would answer a ring I could barely hear the person outside, and they couldn’t hear me very well either. My wife’s iPhone worked fine, much better volume! After being on the phone with Ring support and trying a few different things and nothing helping, I decided to go into the settings on my phone and found the fix. In my SETTINGS >SOUND AND VIBRATION >VOLUME… I found that there were 4 different volume levels, and 3 of them were set low. Attached are 2 pictures. One shows how these settings look if you’re having the problem. The other with the levels all the way to the right is what fixed the problem. I’ll bet this is the problem most people with Samsung phones are having. So go into settings and lock all your volumes to max, as I did in the second image and it should fix your problem!!