Have you recently updated the router's FW ? If yes, then hard reset - (Method 1) and re-configure from scratch.

Can you post a screenshot of your wireless settings. Advanced=>Wireless=>Wireless Settings screen. Just be sure to remove/blur your wireless password from the screenshot, before you post it.

if you prohibit pings from the "outside world", nothing of that you mentioned will happen - you'll still have all the web access as before. It's just a precaution for your public IP address, thus not...

Try these settings for both bands and see if that makes any difference: The other thing you could do is to update your wireless adapter driver to the latest available.

That should be described in details in your phone manual. If not, try to search the Internet for that particular problem.

Try to set a stronger wi-fi password.