The other day - I try to attach an old expansion box (version 1 latest firmware) to a P4 (firmware 7.21) It did not work out well. The PAB recognise the box and allowed it to be attached. When I try to configure the box (after having attached to the PAB system) – I got the answer that the expansion box did not answer. I test 2 different expansions boxes 1. The same result. It works with expansion box 2 however. Is not expansion box 1 compatible with P4?

Sincerely Lasse