Good software development practices would dictate that this be an option and ship the product with the new option
disabled so as not to alter a users
personal settings.
So compromise - make it an option. However, in this circumstance, to appease your developers, then ship the product with the feature ON. Let those of us who don't want our
personal settings changed turn it off.
In my twenty-five years as a software developer AND technical support director I have learned that users overwhelmingly dislike programs messing with their
personal user settings. In almost every case where our developers thought that they "were doing the users a favor" our users complained. The developers incorrectly assumed the user was too stupid to do it themselves. For example if we authored a program and our developers felt that that they should alter the users
personal screen brightness level so the user could see the screen "better" when our program was loaded we would have been flooded with support calls.
If an inexperienced user doesn't realize why there is no sound coming from
a sound producing program, then they probably wouldn't be using MC in the first place. If the user intentionally puts his/her Mute on then
they want it that way - not your way.
I mean c'mon guys it's not like users are clogging up your (non-existent) tech support lines because there is no sound coming from MC because their mute on.
But you DO have users seriously complaining here that they don't want their
personal settings messed with.