Ethernet ports freeze randomly, reboot solves it?

Hi guys

I have had a RB433 and a RB133 both have their ethernet ports stop working randomly..I then reboot the baords and they start working again…

Any1 else experience this? What causes it?

I had the same problem on my RB133s, the LEDs on the NICs would all go off, but the power LED was still on.
The RB would not ping / telnet / winbox, but would work with the RS232 port.

I upgraded the firmware per Normis’ suggestion and only had one problem since, it was very consistent on 1 or 2 websites prior to that.
http://routerboard.com/files/rb-2.18/adm5120-2.18.fwf