The voice commands on my 2017 Model S were working flawlessly until the software update that adding messaging was released. After than, it does great for messaging, translating my words almost flawlessly; however, the voice commands no longer work ... at all! I can press the button and release, and half the time I won't even give me the beep that alerts me that it is listening. When it does beep, I can say, "Call John Doe" and nothing appears most of the time. It just goes back to whatever it was displaying before I pressed the button. I can do it again and it might recognize "Call John" on 1 attempt out of 3. One time it recognized the full "Call John Doe", but didn't make the call.
A command to "Navigate to Fremont, California", or any other destination just is not recognized.
The Jacksonville, Florida Service Center told me this was a known software issue to be fixed in a later release. It must be software, because I was there for them update me to HW3 and the problem still existed when they were done.