Ehhhh...I'm gonna be honest, I don't really get this much. I would think it's a lot more like a water damage problem. Yeah, you may not have spilt a beer on it. But you also more likely got sweat on it. Yeah, I know that sounds ridic, but it definately happens. Also, apparently routers "go bad" that's apparently a thing. So, I would open it up, if you have tools and experience, and check for signs of water damage. Pink/red stickers. Signs that water has washed over something and dried. And replace the antennae. If that doesn't take, it either needs an ultrasonic bath, or board level repair. Here's a guide
Hmm. Looks like I'm gonna need to make a guide...