I have a Mikrotik routerboard RB2011UiAS.
I have an issue that when downloading we only get between 10mbit (1000pps) - 13mbit(1200pps) when connecting directly into the ISP provide with the Mikrotik.
If I put a hp procurve switch between the Mikrotik and ISP provider we get the full 100mbit download, how ever without we only get 10mbit - 13mbit.
Are they any settings or issue with the Mikrotik connecting directly with the ISP?
This might be a ROS bug (what version are you running). Have you tried creating a supout file and involving 'tik support?
As NickW points out this seems like a port negotiation issue.
Putting the Procurve between them certainly goes a long way towards pointing that.
Also, RB2011 has 5 Gbit and 5 10/100 ports. Any change in behavior if you move the WAN port to other ports either on the Gbit half (ie 2-5) or over to the 10/100 side (6-10)?