If any audio on a Web page plays automatically for more than 3 seconds, either a mechanism is available to pause or stop the audio, or a mechanism is available to control audio volume independently from the overall system volume level. (Level A)
Sometimes we observe websites playing music in the background immediately when the page is loaded in the browser. This music distracts the users of screen readers who operate the computer with audio output. The screen reader users will not be able to operate the computer unless the volume of the music is decreased, completely muted or turned off. When I say decrease the volume please note that the volume of the music should be decreased or turned off not the overall system volume. If such option is not provided, some set of user groups cannot perceive any information from the website.
Instead of allowing the music to be played automatically when the page is loaded, it is highly recommended to give the option to the user to switch on / off the audio upon the users wish. If the music is played, it should not last more than 3 seconds. If played more than 3 seconds a simple mechanism should be made available to turn off or decrease the volume such as hitting a spacebar independent from the overall system volume. This turn off button should be placed at the top of the page and ensure that the focus is placed on to this button when the page is loaded. Clear label should be provided for this button such as “turn off music”, “Mute music” etc. If any other page of the website have such functionality, inform the user about the behavior in advance and provide an option for the user to turn off, decrease the volume of the music from the home page in addition to the music turn off facility in that page.
Note: Since any content that does not meet this success criterion can interfere with a user’s ability to use the whole page, all content on the Web page (whether or not it is used to meet other success criteria) must meet this success criterion.