It seems that it's not yet possible to give audio or video feedback for an assignment. However, the feature is being developed and will hopefully be available in 3.6. Please feel free to watch or vote for MDL-27520.
Thank you for your reply!
I was kind of surprised that this is not possible with RecordRTC because we used Poodll up to this point. Poodll does allow for audio and video feedback on assignments. When RecordRTC was deployed in Moodle 3.5, we stopped using Poodll and then found out is was not possible to do this in RecordRTC
Let's hope for 3.6 then. We can't wait, teachers and students were getting used to video/audio feedback. Much more personal!
This seems to be the same issue I am looking into. The record audio option is not available in quiz essay questions. I cannot find anything that documents why the toolbar changes for quizzes and feedback.
Just to confirm that audio or video feedback for an assignment is indeed an option in Moodle 3.6 onwards.
Sean, regarding quiz essay questions, have you tried selecting 'HTML editor with file picker' as response format? You should then see the audio and video recording buttons in the HTML editor.