I didn't realise that was possible. The Sony manual appeared to imply that Auto ISO only works in P and A. I will give that a try as it would serve my needs fine. Thanks.
There is also something weird going on with setting of the max ISO. It can be set from two places: The ISO function; Using the menu. Now I would expect the two places to point to a centrally controlled ISO setting. But randomly It doesn't work that way. Using the ISO function I set max ISO to 32000. Some time later I changed it to 128,000 using the menu. When I was taking photos I noticed the shutter speed was falling below minimum, yet ISO value was only 32000. I went back in the menu and the menu was showing 128000. The I closed out of the menu and checked the Max ISO using the ISO function and it was showing 32000. The two values were clearly not associated with each other.
Well, in that case, as I said above, You must have done something unusual when copying the file to the card. I have owned multiple brands of DSLR's, Mirrorless Cameras and Compact Cameras over the last 25 years. I use a Mac and I have never had a Firmware update fail because Mac OS has written some sort of hidden file there.
Sorry if I was a bit harsh...
In this situation, I would be using Manual Mode with Auto ISO, Set your desired Aperture and Shutter Speed and let the camera set the ISO. I use this mode quite often.