Create a simple Canvas document with a classic tween and sound. Publish with default settings. example: http://www.3rcode.com/HTMLtest.html
When published locally it works OK. When I upload it to my sever there is no sound on Firefox or Chrome. Ctrl/Shift/J shows 13 errors. I am using a PC, Windows 7, and the trail version of Flash CC6. If a simple sound file will not play on Browsers, you will loose sales. I tried pasting in sound code from createjs.com and just got syntax errors.
This problem is not new. See January 28, 2013
It seems that the audio file(mp3) is missing from the server. You may not have uploaded the 'sounds' folder along with the published html and js file to your server.
Can you try again and confirm if it works fine now.