First, yes, I know the organization shouldn't use IE. It's a government project; IE is what I have to build for right now.
PROBLEM: Captivate elearns published as HTML5 only do not play audio for some IE/Win10 users. If published as Flash, the same users do get audio. For others, the audio plays fine in both HTML5 and SWF versions.
There are plenty of organisations still using IE, but any that intend to be viewing HTML5 content should ideally be on IE11, not earlier versions, and if on IE11 they should be using the final minor version of that.
So if you have some users unable to hear sound on IE browser, have you confirmed which major and minor versions they are using? The fact that only SOME users are experiencing issues tends to indicate the problem is on the end user's computers rather than with the Captivate content.
It turns out the fault is some kind of hardware issue with the laptop docks.
Through troubleshooting, we discovered that all the users experiencing audio issues with the HTML5 modules...
- Were using Dell laptops with Dell docking stations
- That the audio played correctly if the laptops were disconnected from the docks
- That the audio doesn't play correctly if the laptops are connected to the docks
We don't yet know the reason for the problem, which persisted after updating all hardware drivers to the same versions as machines that don't experience the issue. We're seeking assistance from Dell, but I wanted to put this here in case anyone else runs across the same problem. The machines and docks in question are common across a number of organizations.