I've had a problem with my PC mouse and keyboard for some time now, at first it started out with one of them randomly stopped working for a second or two, there was even the sound Windows makes when you unplug a USB device, didn't think much of it for a while, only happened when I was playing a game. Then it started happening while my PC was running and I wasn't using it, I'd hear the sound you get whenever you unplug a USB device, found that strange but I didn't deem it a huge problem at the time.
But it's gotten worse lately because my mouse and keyboard both freeze at the same time and don't respond at all while everything else is working and the system is still running normally, that only ever happens whenever I'm playing any sort of game, I have to reset my PC to get them to work, I figured it might have been a Windows update since I was still using Windows 7 at the time and the freeze issue only popped up after the update, got a good friend of mine to install Windows 10 instead and everything worked fine for a few days.
Then the problems started popping up again and got gradually worse, but faster than before, one day my mouse or keyboard would stop working for a second or two and then work fine, then two days later they'd both freeze up, so I figured it might be a hardware problem and not a software one since I started over with 10.
I've had this PC for nearly 5 years now, only thing I had replaced was the PSU and nothing else, open it up every couple of weeks to clear out the dust and never noticed anything out of place, scent of anything being burnt, nothing looks burned either. No strange noises when it's running, booting up or turning off, I'm honestly running out of ideas what might be the problem.