I hope I don't appear out of line here, but I have to be honest. Your problem is being experienced by many others, including myself. You can see on this forum about others encountering the same problem.
Unfortunately, there does not appear to be a solution, and it seems to be a hardware problem with this revision router. If you do not want to go through the hassle of trying to troubleshoot your router, and you still have the option for exchange, I would trade it for a different model. This is a very nice router, but this problem is too common to be ignored.
That's just my suggestion based on reading about others who have experienced the same issue. I have read of no one that figured out the problem was due to a setting in the router. Good luck.
The router has worked well for six months - only a few times it lost connection.
But the last few days I have lost the connection continuously.
Every half hour, not only the wireless connection lost internet also the hardwire connection.
I've followed some of the advice here: I've enable mixed n and g mode, wireless channel 13, channel with auto 20/40, WPA Personal, WPA 2 AES only.
Some of these options was set before, other I just enabled now.
I have many wireless devices connected to the router - wireless and hardwired, exampel smart phones, ipad, TV's, computers, two satelitte decoder, cable TV decoder, Slingbox, wireless land phone/skype unit, Intenet radio box, I'm sure its more.
I begin to wonder if this is too much for the DIR-655 wireless router?
A wireless router is supposed to work out the box, maybe I should look for a more solid wireless hardware?