V2 Pedals / ghost handbrake issue

Hi there - I've found out that RFI on the RJ12 cable is a real problem. I connected my v2 pedals direct to a new DD1, via PS/2<->RJ12 cable that I used to use with my CSRE.

The pedals are detected fine, but in the Fanatec Wheel Property Page, I see a flickering handbrake signal, even though I have nothing plugged into the handbrake port on the DD1.

I can plug my pedals direct into the PC via USB, but ideally I'd like to plug into the DD1 so that I can use the ABS vibrator on the pedals. But Fanatec don't sell a PS/2 <-> RJ12 cable with the ferrite cores needed to eliminate RFI (there is a filtered RJ12<->RJ12 cable in the DD1 box, but the v2 pedals only have PS/2 and USB).

Any suggestions? Has anyone found a filtered PS/2<->RJ12 cable that works with Fanatec gear?

Thanks

David