I have gone 48 hours without any issues since making the NIC change. Not entirely sure as to why this was the solution... I have used the e1000 NIC in this environment for a few years.
So to sum up what I found:
Cause: VMWare Tools update 9.0.12 build-1897911 (Reproduced on multiple DC's)
Solution: Upgrade NIC to VMXNet3 virtual network adapter
@Alistar: Thanks for the comments, I will probably need that script in the future. At the moment our entire environment (150 VM's) is using the e1000 NIC. So I have some hardware cleaning up to do.
UPDATE:
Spoke too soon, issue occurred at the 52 hours mark.