Need help removing buzzing sound from speakers

I have a pair of rokit 5 speakers that give off a buzzing sound when plugged into my computer (the green audio output on the back connected to my motherboard.) I have no idea what the issue is because:

-When I plug my bose headphones into the green audio port, no buzzing sound exists

-When I plug the rokit 5's into my phone, no buzzing sound exists

The motherboard is an ASRock H110M-HDS. I've read that a dedicated sound card may work but I didn't know if the sound port was the problem since I don't get a buzzing when my headphones are plugged into it. Any thoughts?