Why can the receiver of a Magic Jack call not hear my voice?

[AC Question]

With the exception of one person, everyone I have tried to call using Magic Jack has not been able to hear their voice, but I can hear them. However, if they were to be the one calling me, they could hear me just fine.

 

[B. Diddy]

Welcome to Android Central! Is this an Android question? We don't really deal with Magic Jack here--you may want to check out their support page: International VoIP Phone Service Customer Care & Support | magicJack