Default [Q] Galaxy Note 2 WIFI connected but randomly No internet

Hi all,

I recently got WIFI connections in home and my phone wifi is acting kind of crazy.
It connects without any problems but internet doesn't work. I have to turn OFF and ON the WIFI in the phone for couple of times to make it work.
I flashed and running stock 4.3 from the sammobile after the release.
I just want to know it's is just because of 4.3 bug or my router is causing the issue. It works fine with my office WIFI network.
I can use all other phones and computers in WIFI without problems.

Any advice will be appreciated.