I had the same issue the other day, I'd not tried it before. I was thinking of turning the VOX all the way down and then having to use the PTT if we wanted to chat. I do hear the music volume going down but cannot hear the pax talking and they couldn't hear me.

 

Glad to hear it is working

Maybe this is just the first time you plugged in both headsets? Or, just say, wow - what you told me worked (lol)

 

Make sure both parties have the volume turned up for the headsets.