My mic keeps on picking up desktop audio

hi guys, built a new pc last november, everything was fine and all and i decided to pick up a mic splitter like a month ago so i can use my earphones' mic to talk to my friends while i game, so like i noticed an issue when using the mic where it picks up my desktop audio for some reason, tried to fix it by updating realtek drivers, didnt work, this same issue happened to my acer nitro 5 a year back and that was fixed with a driver update, idk what the problem is and idk how to fix it tbh, anyone know how to fix it? tried to look around the web and its just the same stuff i tried, updating, reinstalling drivers, i dont even know at this point i genuinely feel like hating realtek drivers at this point because of how this issue even happens randomly