Q: In the middle of a phone conversation I stop hearing the other party. They hear me fine. I'll hang up and recall, and we hear one another again. The problem is intermittent. I have an iPhone 5.

elcpu, thank you for your suggestion.  However, it did not resolve my problem.  I will be carrying on a conversation when suddenly I will not be able to hear the person.  They hear me fine (they send me a text).  When I hang up the phone and call them right back we can continue our conversation with no troubles.  That is, until the next time the problem arises.  This may be five minutes later or five months later.  Do you have any idea what it may be?