With VE Pro over LAN, there's three main things I discovered recently:
#1) Jumbo Packets definitely make a difference in increasing performance and stability of audio over LAN.
#2) Having a dedicated gigabit network for VE Pro can definitely help but may not be necessary depending on your situation.
#3) Do NOT use "green" gigabit switches!
This took me quite a while to suss out, but I'm sharing this with you having now solid evidence to the claim.
I did a direct comparison between the old grey D-Link switch and the new white one which is "green" (environmentally friendly, energy efficient, etc.). It turns out I was having SIGNIFICANT issues with VE Pro on the "green" switch. I swapped it out for the old grey model and all the problems cleared up.
The confusing part is that both new and old models have the SAME model number! They've silently "updated" the device and made the energy-saving a new "feature" which cannot be disabled, and it appears that store shelves are now only stocking the "green" model and no longer carrying the old heavyweight energy-sucker model.
Just thought I'd share this experience in the hopes of saving someone the aggravation I went through ;)