Rapid error 90000 problems in dungeons

Since patch 2.1 I have been experiencing really bad connection problems.
It only happens when I enter a dungeon, and only once I engage a mob. Randomly I will get disconnected with an error 90000. Once I get back in, ill immediately get disconnected with another error 90000. This will happen over and over until I got vote kicked from the party, or I give up and just leave the instance leading to me logging off in anger! It's frustrating since I'm the raid lead for my bahamut coil party as well as the main tank. I don't know what the new patch did, but I have tried re-installing, resetting router, cold booting my comp, turning off all background programs like anti-virus (which I don't like doing). Strange thing is, I went to a LAN center recently for my last raid, and it happened there too... And not just me but other customers as well were experiencing the same problem. (I live in Southern California, USA)

This just happened to me while in an instance. Along with all the lag, now the game doesn't even want us logged in.