In recent months, I was practicing some pieces on my piano accordion at home for an upcoming musical event I was due to play in with a group of other players. My accordion decided to suddenly have a stuck bass button. A similar fault had happened many years ago (1978 to be precise!) when I was playing in a concert with my Dad and Dad, being a very handy practical person, had done a quick repair on the accordion's innards using a bit of wire and piece of rubber he'd scrounged up! So, on this recent occasion I remarked into thin air "I wonder Dad if this is the same problem"? With that, a musical model I have of a piano, in a different part of the room, started playing. No one else was at home and I wasn't anywhere near the model. I took this to be Dad agreeing with the diagnosis of the fault, and when later my husband helped me take the accordion apart, it was indeed the same problem with another note (a small connector piece had broken), and after all these years, Dad's repair was still in place and still going strong!
And if anyone is wondering how I know which year the previous fault occurred, I have since found a letter I wrote to the music shop the accordion came from, asking them if they could supply a replacement part for the faulty/broken piece, which they had returned to me with the replacement part - which had never been used, due to Dad's excellent 'temporary' repair!