How can I change the default action taken on removable media in Ubuntu?
Solution 1:
Open "System Settings" and navigate to "Details":
From there select "Removable Media" from the left pane. Then you can change what happens when you insert most types of media or turn the prompts off altogether.
More settings can be found under "Other Media".
Solution 2:
You can change the default method for handling these events in System Settings -> Details -> Removable Media.
There is a good tutorial here; http://www.howtogeek.com/117709/how-to-change-your-default-applications-on-ubuntu-4-ways/