We here at Megalith love technology! The latest system we have been building integrates the ability to send and receive voice calls with a click of a button. This is amazing! With Google Voice going away and being replaced by Hangouts, this system is the only surefire safe way to have a private conversation from anywhere in the world.
My computers and devices have built in mics however you probably want call center agents to wear headsets when using this business application. It is secure and protected from abuse. Especially when phone numbers are to remain private (think Celebrities).