Don't know exactly since I have not seen this happening. I've used quite a bit NAT VMs in unison.

Cannot completely deduct the log, but are you saying that NAT is interrupting? I'm asking because if Bridged is the problem, it is completely another ball game.

As for the references to NAT ... don't know, but I found that there is something fishy with that in VMware. I've learned a couple of times, not sure if it was Ubuntu or Windows, that when using a static address, you STILL had to have DHCP active. It doesn't make sense, but it wouldn't work without DHCP being ON. Maybe that notion will help you, not sure?