Mouse and keyboard issues, weird things going on

I've been having problems with my mice and keyboards for a while now. It's like the thngs are haunted or something. Out of the blue i'm typng something somewhere and suddenly I can't type anymore or some letters stop working. Sometimes I can just open another program and I can type in it just fine, if I open the same program I was having trouble typing in again I still won't be able to use it while I'm having 2 windows open side by side, one with, say, wordpad and the other with firefox, I can type anything I want into wordpad but on firefox nothing works or just a couple of letters stop working or whatever (this can happen in any program, not firefox specific). Even worse, sometimes I'm typing something and hit the L button for example and it suddenly locks my computer or I hit the A button and it suddenly starts shutting off. The same thing happens with my mouse, it just randomly goes into auto double click mode and starts opening things on one click or right clicking on left click or whatever odd thing you can think of lol. That's obvously exxxtreeemmmely annoying lol. I have no idea what's wrong with it, it sometimes helps to open my OSK and then it magically works again and sometimes it doesn't. Sometimes hitting ctrl+alt+F9 helps but that's pretty rare. I don't have any weird languages in my keyboard settings. I'm using the latest drivers of my keyboard and mice (which is from the Silvercrest and one mouse is from China, no idea what brand it is, it's just a gaming mouse) but I have the same problem with multiple keyboards and mice so I highly doubt it's driver related.... I seriously have NO IDEA what it could be but it's driving me nuts. Especially when I'm working and my comp suddenly starts shutting down while typing... Could someone help me out with this one?

Anyone any idea? This has been driving me insane for months already.