Using B.
Think it's got to be down me, the cable tester shows the cables are fine and that's why I haven't questioned it! But I tried my small test cable I made up on the laptop just now and it doesn't work on that either!
Off to my local electrical supplier tonight so will pick some new RJ45 connectors up and some stranded cable. I have just seen there are different connectors for stranded and solid cable. Maybe that's my issue.