Slow copy between VM's

Hi guys!

I seem to get a slow copy speeds when copying files between virtual machines.
only 2 to 3 MB/s.
If I copy from VM to the Host running Open Nebula I get about 10MB/s
If I copy from the Host running Open Nebula to the VM I get about 3MB/s

The VM’s in this environment were imported from a VMware environment. Do you guys think there could be a driver issue?

Any help would be great!

Thanks in advance.