Just putting the feelers out, as I have finally managed to get an interview sorted out for next week, two in fact!
I have had a digital card for three years, and it’s been in my wallet and never used in that time.
I remember reading about cards malfunctioning if left in certain positions next to other cards etc, and am mildly concerned that I might turn up to work to find it isn’t playing.
Was wondering if anyone has actually had first hand experience of a duff drivers card?
Second question is (having never used a digital tacho before, though I will be training myself this weekend) how will I know if the card is functioning as it should? Is there a built in test facility on the vehicle unit?
Many thanks
I know one person who had 4 cards fail in very quick succession. There was no apparent reason for any of the failures.
Following the stories of cards failing due to the magnetic fields produced by other cards being stored in close proximity (your wallet) I did a few experiments. Not telling you what I did, but the results were that the chips were unaffected by some very strong magnetic fields 
My driver card has been in my wallet for nearly 5 years and still works perfectly. I’ve noticed that the credit cards stored next to it are ‘maxed out’ and can only assume data from the driver card has affected them 
well, that’s my excuse.
If you’re planning on sticking your driver card in a vehicle unit be careful, what is recorded on the card will be treated as a legal record. If you’re going to stick your card in a VU in a training case, don’t bother - they use different electronic security keys and your card will be rejected (although probably unharmed) by the VU. Likewise if you put a ‘training keys’ card in a real VU, you will simply get an event message; ‘insertion of a non valid card.’
Best way of checking that a card works is put it in a VU. There is a test process carried out automatically at card insertion. There isn’t another process that you can carry out without a VU to check that the card functions correctly.
What an excellent reply, just what I was after thanks. 
Anyone would think you work in this area 
Just like geebee45 I have never taken any special care of my card. If it isn’t in the VU it’s in my wallet alongside other cards. it gets sat on, it gets scanned by the thing on the gate into work when I pass my wallet over it to enter via my ID card which is in my wallet. When I am home my wallet sits on my desk with my mobile sitting on top of it and the card has always worked. I think these scare stories are put out by the people who sell those protective carriers for the digi card to convince people they really need to shell out for one. 
I think you card is either going to work or it malfunctions pretty much regardless of what kind of care you take of it.