• Not sure what is going on but there must be something more at play here. I have also just tested all the above cases again, making sure to remove the card completely from the slot, and still no joy :(

    Out of desperation I even removed and replaced the whole microSD click board from the mikroBUS slot while powered up and I still got the same errors!

    The only difference I can think of is the card detect (CD) pin going low upon card extraction and going high upon re-insertion. I wonder whether that change isn't causing some confusion in the code somewhere?

    I'm off visiting a friend for the next few days so my involvement here could be a bit sporadic.