Thanks for your reply. I want to update the topic; I couldn't follow the link because I couldn't get F4 work as told in the guide (I think because of my keyboard). But I tried another joypad which is identical and that worked just well, really weird.
And I wanna ask another question;
Since raspberry is getting warm I have ordered heat sink with a fan (link is below) but it says running current is 0.2a and I guess that I cannot feed it from directly raspberry pi 3 (for which I have 2.5a adapter), or can I?
@alrdtakn1 This may very well be happening to me and I don't even realize it as I'm using Ethernet. If you haven't done so, download the latest image with the latest firmware and hopefully that solves the problem. I'm afraid that's the only advice I can offer other than disabling the SD card overclock at this time. It doesn't sound like you are doing anything wrong. This isn't the first story I've heard about finicky wifi with an overclock, it seems the included module is very sensitive to certain settings.
@dipkid Poor SNES, now it’s just a boring emulation box with input lag and no cart support. I always wonder what people do with the original OEM board. I assume they throw it in the trash since they never mention anything about it.