Assignment Annotation for PDF when submitted with Audio files

Background

Our academics in one of our Language areas are trying to annotate submitted documents in the assignment module where a written and audio response is required. The presence of an audio file (MP3 in this case) means that the annotation interface does not get rendered. Allowing students to add multiple files of different types including audio and video files without dirupting the annotation tool would be ideal.

Use cases

• Language classes where written and verbal assessments are being conducted side by side. this would allow academics to listen to a verbal assessment, and make comments on a parallel written assignment. 
• Team project work where students need to submit written and verbal files
• Visual arts assignments where written and Multimedia files need to be submitted and graded together
• Any assignment where an audio or visual aspect is used to make the assessment authentic, or where audio or visual componenets are a key component of the assessment

Work arounds tried

• Adding the audio file as a link in the online text box. 
• Adding different types of audio files
• using different types of test files

Suggested options

• Allowing links to not render into audio widgets, meaning either the audio player could open in a pop up when clicked on, or it could be downloaded (first option would be neater). 
• Having the files open up as tabbed "annotation" screens, with audio and other media files opening as a player (this may be less ideal for paralel file marking) 
• engineering the page to handle the annotate action only for files that are: PDF, Docx etc while ignoring the audio or media files

If there are plugins that would assist with this function, we would very much like to know about them.