Noticed when browsing through the preferences, when you select the Codecs as if you were going to change them, and then try to go back to another section such as Chat or Sounds or Appearence, etc, the right side of the screen continues to show the Codec preferences (it never changes). Must close the preferences window and re-open in order to change anything after selecting Codecs.
I can confirm this on my client as well.
Codecs is returning a null value if you do not have any codecs installed which causes the issue you are seeing. If an issue is not created for this by the time i’m off work I will create an issue for it.
SPARK-1172 is very similar to what is being described. Probably wont need to file a new ticket yet