I was using Tomato firmware for months without any problem on a E3000 using a Zyxel P-660RU-T1 as a modem/brdige for ADSL2, with the default MTU 0f 1492 set on the WAN interface using pppoe. However, one week ago I changed my modem/bridge for a Zyxel P-870H which supports VDSL2. The only parameters I have changed are the MTU set to 1462 (provided by the ISP) and the DSL Overhead Value - ATM Encapsulation Type which as been set to none. But as soon as I changed those parameters, my ps3 has started complaining about "Router in use may not support IP fragments…". However, if I connect direct to the Zyxel and configure it as a router (with NAT), I don't have this message anymore. Why do I have this message when connecting from my E3000 with the Zyxel as a modem/bridge ?