I''ve been modifying GustavoM's Bastion sound pack with some of the sounds from the Dota 2 announcer packs and now I'm getting an error message from the files i modified only. All I did was replace existing files with new file named exactly the same thing, but all I'm getting is this:

"An error has occurred: This is a sound related error. Please make sure your sound drivers are up to date. You may want to go under options and change the audio device being used. See our forums for more troubleshooting.

Could not determine container type!"

Any ideas as to what I'm doing wrong?