WIZ750 ethernet switch problem

I have been using the WIZ750SR Ver 1.2 for connecting several TTL devices in a network. They are connected through an unattended ethernet switch.
Recently I have swapped to the WIZ750SR-100 (due to form factor). However these don’t work the same way. I initially suspected the ethernet switch (I am using a BotBlox-Switchblox). But it does work fine with the WIZ750SR.
When checking the network with WireShark I can see that the WIZ750SR-100 floods the network with broadcast messages and block any other device on the switch.
I would appreciate help with this issue.

when you change from WIZ750sr to wiz750sr-100, are you use the same schematic?
The latest version of f/w we are currently providing v1.3.3
Could you please upload the latest version?

Thanks for your response.
I have been using f/w v1.3.3 that came installed in the device.
Why would the WIZ750SR work but the WIZ750SR-100 wouldn’t?
Please help.