My PUBLIC interface, conected to Internet with Fixed IP, is having more trafic that LOCAL interface , conected to LAN. The trafic is going through from PUBLIC to MikrotiK, but it doesn´t go out to LAN in same numbers.
In attach, picture of Interface windows.

Please, if anyone can help me to discover what is the problem!!!

use Tools -> Torch to see the traffic

OK, but what kind of trafic is wrong?

but what kind of traffic do you see? =)

I have set a lot of firewall rules that found in the forum and it look like to stopped. Thanks a lot for your help.

Finally I created a firewall filter to drop :

Chain: INPUT
DST address: (Public IP)
Protocol:6 (TCP)
DST Port: 3128

I could see that this traffics still hapen when I disconect LOCAL interface.

Somebody know what is the problem?

somebody from Internet uses your router as a proxy? =)

do you run proxy on port 3128?

I don´t have PROXI setup.

Is that interface on a hub?

The interface public is conected to Internet by static IP.

I mean what type of device is it plugged into.
Hub, switch, router, etc.

It is pluged to Switch with one PC with fixed IP too.