No you don’t have to stop it. There is actually a cache which should actually stop scanning the redundant/repetitive scripts, see more here: http://forum.avast.com/index.php?topic=83740.0

So let us try and go a little bit deeper, please answer the questions:

Which version of avast do you have?

Can you post a screenshot of the activity?

On which website are you listening to music? - Please give us the link.