I'll be cross-posting this to the BCAB email list because I'm not sure if it's an NVDA-specific issue, a windows update issue or a Dell-laptop issue.
Let me explain what is happening.
Yesterday I had a friend visit who had never heard a screen reader before, so I demonstrated my NVDA using the Microsoft SAPI 5 voice Zira. I also changed the symthesizer to the E-Speak one and used the Lancashire voice before changing back to SAPI5 / Zira.
Windows also picked yesterday to do an automatic update. I am now running Windows 10 Version 1803 (OS Build 17134.829)
What is happening is that the volume using the Microsoft SAPI5 voices Zira and David are flucuating wildly in volume. I do have NVDA set to duck when outputing speech and sounds but even when I turn ducking off I'm still getting very large spikes in volume when typing.
For example, as I am typing this it was at my usual nice listening volume but then I went into the NVDA menu to look at the speech settings again, and the volume in the menu jumped and got much harsher (Zira is quite a soft voice at my usual listening volume). I pressed ESC to come out of the settings and it remained loud and harsh for several bits of typing before settling back down to the mor normal volume level. Let me see how long it takes for the volume to rise again ... and it is already harsher and louder ... and will drob down and softer now. It's all very strange! I am writing this in Notepad.
I recorded the Zira voice reading most of that previous sentence and it still sounds exactly the same as in the recording, it starts at a comfortable listening volume and quicly gets louder and more abrasive..
Can anybody tell from the recording (link here with the url broken up with three spaces so it works on the NVDA group webpage) what might be happening.
http:// gilesturnbullpoet.com /wp-content/uploads/ 2019/06/NVDA-post-Win-update.mp3
It is most likely that I have inadvertenly changed a voice setting (though all settings seem as they normally are), or that the Windows update has tweeked something in the SAPI5 and Core1 voices, or has upset something in my Dell Latitude laptop sound drivers.
I'd be extremely grateful for any ideas that I can try to fix this problem.