so i was in a voice chat.
person a. cannot hear me but i can hear them.
person b,c,d,e etc. can hear me speak just fine and i can hear them.
i do not have my voice turned down.
person a does not have me turned down.
we tried changing the obvious settings in discord nothing worked.
only things i can think would make it so person a could not speak to or hear anyone so im stumped.
we tried restarting both our computers. didnt work.
I don’t think person A is being honest about the volume they set you at. 
But really, if you have Discord problems, you should reach out to their support.