Thanks Fishy - I installed the TT A4 sound profile from the list whilst in Bluetooth which I assumed was the correct one, but could not get Dcc to work on the app. I managed to get it working on the Power Cab by altering the long address, but this is only on a small programming track, I think I had got confused between long and short addresses, my fault, the thing is it appeared to move only slowly on the programming track but this is only a short length of track and my not be long enough for it to accelerate correctly, perhaps with a longer length of track it would accelerate correctly, I will try with a longer length of track. The auto calibrate is that done via the app and if I put it back on the app using Bluetooth will it effect it on the Dcc using the power cab