I want to say it was great to meet so many Canvas users at the OLC conference last week as well as the InstructureCon event! Many of the our booth attendees commented that the free TTS reader in Canvas is limited only to Pages, which means a majority of their content isn't accessible. This is a great example of "free isn't always better." I encourage you to watch my session at InstructureCon (available on demand) that gives a good overview of the ReadSpeaker TTS suite of learning tools. Reach out if you have any questions.
I m very concerned about the students using this feature in the Foreign Language Classroom. There should be a way for the teacher to be able to disable this feature.
This is a discussion to have with your faculty senate or other such group to decide if your institution would like to have specific tools such as Translate, Dictionary and Download to mp3 turned off for all Canvas courses at your institution using a specific Canvas theme. ReadSpeaker support will be glad to assist you.