Does Canvas transcode audio file submissions?
My students are submitting MP3 and AAC/MP4 audio files for their final assignment, but when I download their submissions through SpeedGrader, I'm getting lower bitrate than what they had originally uploaded. Plus, the files all appear to be transcoded into AAC/MP4.
So if a student uploads a 320Kbps MP3, Canvas provides the instructor with a 128Kbps AAC file instead, losing quite a bit of high frequency information. The files are about 1/3 the size of their original upload. This is a problem, since the students are being assessed on the quality of their recordings.
Is Canvas transcoding these files or assigning the wrong file headers? Is there an option in Canvas to prevent this from happening?