Linksys Wireless Router :: E4200v2 Connection Always In Dead Loop

I've bought my E4200v2 via eBay, because original Cisco store doesn't ship to my country (Israel).My first unit was... defective, I think I wrote about the issue on this forum a while ago.It had connection troubles, always in a dead loop, saying "Connecting..." one to 100 times it managed to connect, and suffered slow internet connection speed, where all speedtests gave me 60% of my actual internet speed.Which is 30mbit.I'm sure about my ISP, it uses next.gen technology, they have their own underwater optic cables. Without Cisco router, only dialer, I get 100% of my internet speed, or with another router as well.I decided to RMA my e4200v2.

Out of context question: Why there's no option to specify server name instead of server IP? our ISP uses domain name for connection, rather than IP address, as they have a lot and a load balancer above 'em.Now, to the original issue.Refund is no option, RMA again is no option, too much time and money.Maybe there is a solution? It just can't be the reality, that two out of two units are not working. I heard this router is very good. And I heard the v1 is working very well in Israel. so It can't be our country that is the problem.By the way, I've called my ISP and they've switched me to MPLS connection for a try, so in a router you just switch to "Automatic configuration - DHCP" and it pulls IP, DNS servers and connected to the internet, but was hooooribly slow.
 
So I'm back to dialer. the main still is the "Connecting..." loop, sometimes says "Connected" for a second, and then connecting again... It manages to pull DNS addresses though, but never the IP and never managed to stay connected.All the connection configs are very basic, you know it. Server IP, username, password, keep-alive, MTU (I've tried auto, and a ton of other combinations recommented by our ISP or Cisco).My latest idea was to film how I burn it or throw a rock at it and send to Cisco the video, but that's kinda too much, it's too early for such decisions, especially when already $300 were spent.