One way audio Issue with supervised transfer

Greetings, I run several Freepbx systems and I have just one that is having this very particular issue. I was hoping someone could provide some words of wisdom.

When a user initiates an attended transfer and they hold on to speak to the other user before they fully transfer the call over there is a one way audio situation all of a sudden where the person doing the transfer cannot hear the transfer destination. However once the call is fully transferred everything seems to be fine. Also I am not aware of any other 1 way audio issues they are having.

Reinvite is not on anywhere and this is a hosted solution so everything is passing through a firewall.

Thanks in advance.