How do I insert a sound that plays automatically on all devices in RSD?

Use an html element and use this code.

While the above code will work, please keep in mind that auto-playing sound in websites is a pretty big no-no. Most visitors to a website are not expecting auto-playing content and will not appreciate it, with exceptions for websites that are explicitly designed for playing content (like Youtube).

Another thing to take into consideration if you absolutely must have music or sounds loading on webpages automatically is to include an on/off switch for your visitors so they can at the very least turn it off if they don't want it there. There's nothing that will scare away a visitor faster than music that someone hates a style of, is too loud, can't be turned off, etc. etc.

Give them a way to turn it off and you may save at least "some" of your visitors.

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