Default Wifi disconnecting on Android 4.3

I've searched a lot over the past couple of months but haven't find an answer to my problem.

When I connect to public open wifi networks that have a landing page, phone would automatically disconnect and display a notification saying "Sign-in is required. Network disconnected". This only happens if I turn the wifi on and let it scan and connect automatically. If I manually connect to any such network it'll automatically bring up the landing page instead.

I have disabled network quality check in the settings, but that doesn't solve this problem. I also installed the new firmware with a full wipe and cleared wifi hotspots a couple of times (TB).

Anyone else has had this issue and knows how to solve it?
Thanks a lot!

Sent from my GT-I9300 using xda app-developers app
Android 4.3 XXUGML2 (rooted)