Few Ethernet LAN clients not getting IP

Hi All,

We are facing an issue that few ethernet lan clients when connected to cable modem box is not getting IP for example an windows client is getting IP but other client of same version of windows client is not able to get IP, tried switching ports, factory rest etc, it is observed that the DHCP discover packet is not reaching the brlan0 interface. anyone faced this  kind of issue or any pointers to debug it further below layers is much appreciated.  Thanks