Text-to-Speech option stops after reading a portion of the overview panel

Steps to reproduce:

1) Open the prefs framework demo
2) Open the display preferences panel
3) enable text-to-speech and listen to it read out the page
Notice that it stops reading after "... and delivery environments"

However if you refresh the page when text-to-speech is enabled. It will continue reading the contents of the page from "Notes: The 'text-to-speech' ...".