Nothing, just a single Panasonic base station plugged into the Hub3 with the same RJ11 cable which works fine with a BT Decor 2200v2 on the end of it. The wireless Panasonic handset (the base station does support multiple handsets, which is why we want to use it, but ATM there's only one active) immediately comes up with a missing line error message and there's no dial tone, but there's no configuration settings. I'm an AV engineer, so I'm happy with my fault finding. The cordless was working fine on the old twisted copper pair, so there's nothing I believe faulty, but according to my limited knowledge of phone lines, a 600 ohm phone line is about as basic as it comes, so I'm not sure why one device works and the other doesn't...