I'm not sure what you are saying. I'd have thought that as the drivers are part of nvda, at least when it updates, it has to do a restart and hence cannot speak.
In the case of windows updates when windows does this it normally runs in a mode where as few bits of windows are running as possible, so it can update system files and then reboots. So are you saying that this loses the paid for voices unless you deactivated them before the update then re enable after it? That would seem a little odd since most registered software seems happy to re initialise as windows reboots.
What are you trying to hear during the update process, as of course Narrator can be set to at least talk some prompts, and maybe finding a different default voice might help, but unless Microsoft are going to do an Apple and put in Eloquence as standard, you are probably stuck with whatever happens here.
Brian

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