Ok, so I made an interesting discovery. When I dd($request->file('file')); I get the following output (with the correct mimeType data):
UploadedFile {#187 ▼ -test: false -originalName: "CUS2398472-20-AUG-2016-13-48-43.mp3" -mimeType: "audio/mpeg" -size: 47000471 -error: 0 path: "/private/var/folders/c7/6ws0lxy95dd_lhz1k067_zkc0000gn/T" filename: "phpkit5Rg" basename: "phpkit5Rg" pathname: "/private/var/folders/c7/6ws0lxy95dd_lhz1k067_zkc0000gn/T/phpkit5Rg" extension: "" realPath: "/private/var/folders/c7/6ws0lxy95dd_lhz1k067_zkc0000gn/T/phpkit5Rg" aTime: 2016-09-19 18:06:14 mTime: 2016-09-19 18:06:13 cTime: 2016-09-19 18:06:13 inode: 4251949 size: 47000471 perms: 0100600 owner: 501 group: 20 type: "file" writable: true readable: true executable: false file: true dir: false link: false }
But when I call the getMimeType() I get the "application/octet-stream" output. So the Laravel method is returning something different than what the uploaded file is providing. I've added "'audio/mpeg' => 'mp3'," to the array in MimeTypeExtensionGuesser.php. Any suggestions?