Symptoms
The follow error message appears when trying to play video or audio:
** Message: Missing plugin: gstreamer|1.0|totem|MPEG-4 AAC decoder|decoder-audio/mpeg, mpegversion=(int)4, level=(string)2, base-profile=(string)lc, profile=(string)lc (MPEG-4 AAC decoder) ** Message: Missing plugin: gstreamer|1.0|totem|H.264 (Main Profile) decoder|decoder-video/x-h264, level=(string)3.1, profile=(string)main (H.264 (Main Profile) decoder)
Solution
There are missing multimedia extras plugins on your system. The fix is easy as execution of the following linux command. Open up terminal and enter:
$ sudo apt install ubuntu-restricted-extras