I/O communication error

Good Day,
I have some I/O communication issues with my Allan Bradley 1756-L72 ControlLogix5572 Controller Running the RSLogix5000. Every so oven I get the I/O not responding message for no certain duration of time. It's never on the same module twice and never favors any of the ETAP or the FLEX modules, the yellow warning triangle always shows on top of the Configuration tree at the I/O configuration and then another one jumps between the modules down the line at a different module each time the problem exists. Only for short periods of time and then recovers it self. The problem comes in when it happens to some of the FLEX modules witch operates critical relays in the system it seems like communication to the module is lost.
I've captured screenshots of some of the module properties while the fault is active "[Code16#0204]Connection Request Error. Connection Request timed out."
# Checked the system voltage to all modules 24.8vdc
# Checked the connection status on the module while the problem exist all ok.
1) Could this be an configuration setup problem?
2) Where can I start looking or maybe detect the problem?

I've seen these symptoms associated with a failing Ethernet switch.

I had this on an old plant where all of the ethernet cables were in the same cable containment as the motor cables.

I couldn't change the containment, so I changed the cable to a fibre optic and the problem went away.

Cheers

Mark