Sorry, I don't know exactly where the issue lies; feel free to refile. However, as noted at https://commons.wikimedia.org/wiki/User:Dispenser/Wrong_Extension, there are several mp4 files claiming to be .ogg
https://commons.wikimedia.org/wiki/File:2dschrodinger.ogg is very recent (April 7, 2013), and uploaded through UploadWizard (but not sure if the issue is specific to that).
Commons shows it as "MP4 audio/video file, AAC/h.264" and downloading confirms that. It is not an ogg in any way (not even mp4 in ogg).
mp4 is not an allowed file type on Commons (https://commons.wikimedia.org/wiki/Commons:File_types).
Version: unspecified
Severity: normal