Audi Coventry run the diagnostics and found no faults. So I went to Rugby services to try their 350kwh charger... and it charged perfectly. Then I realised that the charger cable was on the right and plugged easily into the DC charging port on the right (drivers) side of my etron as I had entered the bay nose first. I recall the chargers that had been problematic at Woolley Edge and Wetherby had cables on the left side and it was quite a stretch to drag them across the bonnet to plug in as they wanted to retract. So I surmise that was the issue i.e. the charging cable was not properly seated. Next time I will reverse in if I use these chargers.