No type declaration

I have followed the tutorial about making sounds.
(this one: http://www.kirupa.com/developer/as3/playing_sounds.htm )

I have no errors but i have 5 warnings, 4 of them stating that function ’ ’ has no type declaration. How can I resolve this?

The last error states that soundClip will be scoped to the default namespace: sounds :internal. It will not be visable outside of this package.
What does this mean and has it anything to do with the sound not playing when I test the file?

Thanks for reading ^^