As previously stated I tried hardware v8 and v10. I can't imagine v9 will make a big difference?
And yes, I tried both VI and web client.
Well, I got the VMs needed for this project and am not able to spend more time on this problem as for now. Hope that someone with more time to debug runs into this 
Sidenote: the error started with Intel nic too, had to deploy the last VM manually.
Thanks for the suggestions!