Could you do a little test for me? If you run the sketch UDPSendReceiveString (an example from the ethernet lib) then send it artnet, what do you see in the serial monitor
Ok the udp lib samples in arduino 023 are working ok, no freeze
I have letted a led system plugued to an arduino with my sketch one hour without freezes
Readen your links
I would like to know at wich rate you are sending from vvvv ?
Avoid continuous sending (but we discuss previously of this) with low hardware.
You should try to set a volatile boolean index to 1 while writting the buffer to store dmx data,
And do the job of sending i2c in a timer, when the boolean index==0
This to avoid write and read the dmx array at same time. Its a littlebit more code nut i believe it could be the solution
Once again avoid arduino 1.0 and prefer 023 version wich works with uno. Maybe part of your problem is there