My range extender has been installed for about a year and got a lot slower. All the leds are lit green. The router has a speed of 177 MBps but the extender puts our 20 MBps. Do I need a new device?
The wn3000rpv3 is a n300 range extender. That means is a single band wireless 2.4ghz extender. Many different devices utilize 2.4ghz as it has good range and penatration. Problem is that is lower bandwidth and that it does broadcast so far. this causes interference. As wireless devices get added to your area, so does wireless interference. You can try going in to change wireless channels to see if it helps with wireless interference.
I usually recommend people to download either a pc program (there's free ones) or a phone app to do a wireless channel scan to try to determine the best channel to be on. You want 1-6-11. the other channels might have less broadcasting on them but there's channel overlap. so go for the one with the least amount of devices broadcasting on 1-6-11.
other thoughts is that hvac, foil lined insulation, metal devices (tv backings/etc), do a great job within a house of blocking signals. Sometimes moving extenders to a different room can make a big difference.
Another thing you can check is your firmware. make sure you're on the most current.
