There are only 4 lines (only Line Out 1 and Line Out 2 do anything) and none of them work for the headphone jack in my DDJ-FLX4. I have tried switching around the lines, devices, and sound cards, and nothing has fixed it.
That looks correct. Are you certain you have the phones volume on the DDJ turned up, and that it's set to cue? I'm sure you have, but have to start somewhere :) Also, do the phones work when they're set to master?
Indeed settings are correct. Just tested and no monitoring issues on my FLX4. Do you have other controllers connected and if so which ones? Additionaly, what TP4 version do you have installed?
A short video clip of your full setup should help.
Problem solved by user.
@Hunter111 you should mentioned it here, not in forum reports… :-)