I really need help, so i have a ps4 and a pc connected to the same monitor. The ps4 is HDMI while the pc is DP. I have a set of speakers connected to the monitor, but the pc doesn't output any sound, while the ps4 does.
The Display Port likely is not passing audio to the monitor. Check the manual and see if that is the case. You may need to use the headphone out on the PC and connect that to a 3.5mm audio in on the monitor.