Slow internet Link

Im fairly new to routeros and need a little help. I deployed the vmware cloud hosted router .ova as per the download link for version 6.41.
I started it up, gave it an internal ip and an external ip pointing to my internet gateway with traffic NAT’ed between internal and external. Now my line connection is 20mps fiber and it tests out at 20mps up and down consistently. However whenever I connect through the routeros virtual I get only 2mps up and down. I put a windows machine virtual on the system with the same IP addresses and get 20mps without issue. I also checked the MTU settings are as per ISP recommendations. This is literally an ‘out of the box setup’ so I was wondering if there is something I am missing in the setup and it seems a little odd to be limiting speed like this. Please help.