Are you able to post some more details of which adapters got what IP address etc??
Are you able to determine whether the IP was DHCP provisioned (the new one that you noticed)?
Normally you should leave the MAC addresses to be automatic if you know what is what in your setup.
Can you confirm on the esxi host using 'esxcli network nic list' that all NICs on your host are as expected, have go the right MAC addresses etc?
What else has changed in your setup has anybody swiched the cables or something?