Fabiano, all right with you.
To solve the ether down problem after replacing the UTP cable cat5e by Furukawa cat6a and continue problem, I ended up choosing to downgrade the mikrotik (ccr1009) version of 6.36 to 6.35.4, was still not good because he had lost packages around 5%, so did the downgrade mimosa version of 1.41 to 1.31, so it was better with the loss of 1% of the packages.
The solution on a lead was to install a tp-link swich linking to B5c where loss of packet loss disappeared at 0% and troubleshooting.
In other other call with mikrotik rb3011, the loss was still 1% after downgrading mimosa B5c to 1:31, my conclusion is that the firmware B5c has bugs and does not work with mikrotik because the radios smart wi2be, SIAE ags20, airfiber 5x not have any problem with mikrotik.
But because of this problem I will be required to purchase swich netonix to solve my problem, and that problem of Mimosa B5c.
Regards Paulo Oxley