RB493 as bridge/switch stops passing traffic

I have several RB493’s set up as switch/bridge that sometimes decide to just stop passing traffic. The RB itself remains reachable, etc… but it doesn’t pass any traffic THROUGH it. These are configured as a bridge with some simple firewall rules. This only happens on about half of the 493’s that I have. I’ve tried ROS v3.10 through v.328 and still get the same results. It can work fine for days or weeks and then just stops. A reboot fixes it. If I replace the 493 board with another one with the exact smae config then the problem goes away completely. The problem is very frustrating as from my end everything looks green but the customers connected to the board have no service.

Any ideas or similar experiences?

You might want to check out http://forum.mikrotik.com/t/rb493ah-ethernet-ports-stop-routing-then-restarts/26396/1 to see if you have experiencing an issue that others of us are.