Originally Posted By LatinoMike
All we know about this update is what is on the official Ketron page. Perhaps Ketron should provide a detailed description, as other compaines do, about what problems their updates are intended to fix.

https://www.ketron.it/en/software/54-audya-5/audya5-5-4c


They do tell you on the very page you linked to:
"1 Improvement and optimization test harwar and software."

That means its a minor upate to address some test issues.