This might not turn out to be an NVDA issue, but ...
I use the Kindle for PC with NVDA as well as my phone to read Kindle books. I just purchased one which, when I open it, a voice automatically starts reading at a speed that I did not set. It is apparently the tts that goes into action when the Kindle app starts reading something, kind of like what happens when you tell Acrobat reader to read out loud.
In the case of this book, NVDA sees no text at all. All the menus work. But when I do an insert down to start a read all from the selected chapter in the table of contents, nothing is read by NVDA. On my phone using the Voice Over screen reader, this book reads just fine, thank you very much.
I am aware that there are a few books that you can't read with a screen reader, period. But this doesn't seem to be one of those, since it is working fine on my phone. Is there some setting I'm missing that would allow me to use NVDA and my preferred voice and speed over the speech that comes from the Kindle program itself?