Audio is not directly supported in Axure, except with inline Frame widgets (which I consider to be indirect support as there are multiple dependencies for this to work.) I, along with other users have had some success with javascript injection methods, but those are not officially supported by Axure (meaning they work, but if something goes wrong, don’t expect support from Axure.) As you’ve found, these can be tricky to use, especially on mobile platforms, which now block autoplaying audio and video at least until the user interacts with the page.
If you can upload your .rp file it will be way easier to help you. If not, could you save out a page or two to a new .rp file, strip anything confidential, and upload that?
Just when and why do you need the sound to play? Are you trying to get sound to play when page loads? That likely won’t work on iPad. If the sound needs to play only after user does something, that should be possible.
Here is a link to an old thread that I updated last November, showing several methods to play audio. You can test the live Axure Cloud link on your iPad to see if the sound works:
So, how did you get it to work on your mac? Inline Frame? Javasript? Other?
Where is sound file located? Locally on your mac or on cloud/server somewhere? If former, then you need some way to get the sound file on your iPad and properly refer to its location–or embed the entire sound into prototype (more on that later.) If sound is online, have you ensured the iPad has access and that the server doesn’t somehow block mobile/embedded access? Test by opening the URL for the sound in a browser on iPad–does it play? Does it play automatically? The iOS blocks videos and I believe audio on a webpage from playing automatically without user interaction.
How are you accessing the prototype on an iPad? Using Axure Share and Axure app? If so, a javascript plugin to play sound on page load is probably a good approach.
Or, is prototype otherwise installed/downloaded to iPad? In the past, I’ve used offline browser apps (which let you zip up a webpage or site and transfer that zip file to iPad via iTunes. If you place sound file in the prototype’s root folder (same place as start.html) then you can open it in inline frame as an “external page” and simply paste in the filename.
Will iPad have internet connectivity? If not, then embedding the sound as base64 is probably the way to go. This thread has details: