Layer 2 MAC address connect fails in WinBox (Internal Error)

When I connect a patch cable directly from my laptop (Ubuntu, Winbox via WINE) to a MikroTik router and attempt to connect using the MAC address via WinBox, I get an “Internal Error” message, and no connection. This used to work. I have attempted to fix by installing a different version of WINE, and re-downloading the binary. Has anyone seen this error before? Working around this is making life more difficult.