Voice guide issue or limitation?

[Nocturne64]

Hello, I just purchased my new CVP809. After 2 days I'm very very happy with it. Fantastic voices, superb styles, piano voices are really well sampled, so playing solo piano classical music is a joy, too.
But I have an issue that I'm not able to address.
I must use Voice guide feature due to my visual impairement. It works well, but it seems that some important screens are not spoken.
For example, voice does not speak all mixer options, so setting EQ, effects, echo is very difficult for me. The same in Keyboard screen, and maybe in other screens. I must check carefully which screens are affected, but the problem is present in some important feature of the piano.
I just tried to download Voice guide file again from Yamaha web site, tried to format my USB key and copy all files again, also I connected and tested a different key, but no way. I suspect these screens are not supported by Voice guide, and this would not be a good news for me. Obviously main piano language is set to English.
Anyone tested or can test this issue? Thank you.