If you are trying to connect by WIFI you may be too far from your server. If you get a good WIFI signal at the tv you may have the password typed in wrong. Easier to do than you think. If you can hook it up wired try that and that will tell you if the TV is the fault or the WIFI.
I have a noise coming from the right side of the 58L9300 TV when the TV is on or off. The only way to stop it is to unplug it and then after a few seconds it starts up like a fan.