When using my speaker phone during calls on my HTC One E8, my callers can't hear me. How can I fix this?

[AC Question]

When using my speaker phone during calls on my HTC One E8, my callers can't hear me.

HTC One E8 through Spring cell service - HD pops up on the phone during calls completed through the speaker phone option.

 

[dpham00]

Re: When using my speaker phone during calls on my HTC One E8, my callers can't hear me.

Does it work ok using the ear piece?