Hello, this is Emily.
How do you connect your monitor to the computer? Is it an aux port on the monitor itself?
Since it is connected via the monitor, it is not the realtek driver you need, but the GPU driver. The sound on the monitor is fed by the GPU. In addition, some monitor could have local settings to disable/enable the sound. Make sure you look into that as well.
What graphics do you have? Do you have both integrated and dedicated ones?
no, i just connect my monitor through the hdmi cable that goes from my gpu hdmi port to the monitor. I have 2 aux ports, one on the back of the case and one on the front of the case near the other usb ports. My gpu is a gtx 1050ti which has right now the latest driver(2 days ago everything was working and I still had the same driver, so that wouldn't be the issue in my opinion). The monitor hasn't been touched so no setting has been changed, I'll look into it just to be sure but I hardly doubt that would be the issue. My cpu (i5 8400) has an igpu but it has never been used and my gpu as i said above is a gtx 1050ti with the latest drivers.