.mp3 file type blocked in multisite

Support
1

Strange bug

I’m trying to upload .mp3 files but I’m getting the following error:

Sorry, this file type is not permitted for security reasons.

Wordpress version: 4.7.4
Multisite (sub-domain)

Side note - mp3 uploads work in non multisite install

Here is the output from get_allowed_mime_types() note mp3 is included

'jpg|jpeg|jpe' => string 'image/jpeg' (length=10)
  'png' => string 'image/png' (length=9)
  'gif' => string 'image/gif' (length=9)
  'mov|qt' => string 'video/quicktime' (length=15)
  'avi' => string 'video/avi' (length=9)
  'mpeg|mpg|mpe' => string 'video/mpeg' (length=10)
  '3gp|3gpp' => string 'video/3gpp' (length=10)
  '3g2|3gp2' => string 'video/3gpp2' (length=11)
  'mid|midi' => string 'audio/midi' (length=10)
  'pdf' => string 'application/pdf' (length=15)
  'doc' => string 'application/msword' (length=18)
  'docx' => string 'application/vnd.openxmlformats-officedocument.wordprocessingml.document' (length=71)
  'docm' => string 'application/vnd.ms-word.document.macroEnabled.12' (length=48)
  'pot|pps|ppt' => string 'application/vnd.ms-powerpoint' (length=29)
  'pptx' => string 'application/vnd.openxmlformats-officedocument.presentationml.presentation' (length=73)
  'pptm' => string 'application/vnd.ms-powerpoint.presentation.macroEnabled.12' (length=58)
  'odt' => string 'application/vnd.oasis.opendocument.text' (length=39)
  'ppsx' => string 'application/vnd.openxmlformats-officedocument.presentationml.slideshow' (length=70)
  'ppsm' => string 'application/vnd.ms-powerpoint.slideshow.macroEnabled.12' (length=55)
  'xla|xls|xlt|xlw' => string 'application/vnd.ms-excel' (length=24)
  'xlsx' => string 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet' (length=65)
  'xlsm' => string 'application/vnd.ms-excel.sheet.macroEnabled.12' (length=46)
  'xlsb' => string 'application/vnd.ms-excel.sheet.binary.macroEnabled.12' (length=53)
  'key' => string 'application/vnd.apple.keynote' (length=29)
  'ogg|oga' => string 'audio/ogg' (length=9)
  'wma' => string 'audio/x-ms-wma' (length=14)
  'mp3|m4a|m4b' => string 'audio/mpeg' (length=10)
  'wav' => string 'audio/wav' (length=9)
  'mp4|m4v' => string 'video/mp4' (length=9)
  'webm' => string 'video/webm' (length=10)
  'ogv' => string 'video/ogg' (length=9)
  'wmv' => string 'video/x-ms-wmv' (length=14)
  'flv' => string 'video/x-flv' (length=11)
2

Hi Steven,

That’s definitely interesting.

Are you running nginx or Apache?