Try changing your router’s broadcast channel

Most cordless telephones have a little button on the handsets which you can press to change the channel if there is noise on the line. Like cordless telephones, routers broadcast on many channels too. You may be experiencing weak or noisy signals simply because your router broadcasts on a channel that doesn’t work well at your location. Try changing the channel. You will find an option to change the channel in your router’s administration interface.

If fixes at the router end of your network don’t work very well, you can try fixes at the other end — your computer.