Q: I have the Iphone 6 Plus and I am having a hard time hearing the other person

Greetings tsmiley67,

Welcome to the Apple Support Communities!

I understand that you are having difficulty hearing other people from the receiver on your iPhone 6 Plus while on calls. To troubleshoot this situation, I would recommend reading over and working through the information located in the attached article. 

If you can't hear a person on a call or voicemail or if the sound quality is poor on iPhone - Apple Support

Cheers,

Joe