Paul (and anyone else who uses Sony cameras) I would like to suggest that you test out Capture One for processing your RAW files.
I have found it does a better job of handling the Sony files than just about anything else. Also is GPU accelerated.
My experience is based on the Sony RX10 files, and a friend of mine who uses it for handling his A7Rii files.
A free version is available for use with Sony RAWs; or you can upgrade to the full version of the software at a low price. Just a happy user, I have no financial interest in the company.