N600

I have had a N600 WNDR3400v2 for about a year. About 3 or 4 months ago it started to drop connection. I have an iMac and an iPad connected to the router wifi. The drops have increased the last month, and can now can only get a few minutes at a time if at all after reseting it. Most of the time the four light turn on into the green or blue color. Than the internet light, the one next to the power light, will go out. Other time the two wifi lights will go out. When I reset/repower not always does it turn back on. Some times no lights will turn on other times a few light will turn on but very dim. I will wait and nothing happens. I will have to wait awhile and even then I will have to keep turning it on and off before it will reboot. I have tried changes settings, I have turned off auto channel, lowered Mps. But to chance settings I have to be connected to the internet so to change one thing before it drop takes a very long time. Hard wire works great, no problem there, no other channel close to mine in the area. I tried talking with Netgear but all they wanted was my credit card number before even listening to me. Would have to pay more to get the lifetime warranty. Please give suggestions that might fix my problem. Thanks in advance.