It seems that you're using an outdated browser. Some things may not work as they should (or don't work at all).
We suggest you upgrade newer and better browser like: Chrome, Firefox, Internet Explorer or Opera

Do you have any programs running in the background that take up a lot of system resources such as an antivirus program or anything of the sort? Have you tried updating your sound drivers? Have you installed the game outside of Program Files and are running it as administrator?

If you continue having sound stuttering problems, please contact our Support deaprtment with a detailed description of the problem and a DxDiag attached to your email. Thank you for your patience :D