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
CreateJS No Sound in Browsers / SoundJS / Discussion Area - CreateJS Support