I've been trying to make an audio tag work in as many different browser/OS combinations as possible. Here's the simple snippet of code I am using:
<div class="audioPlayer"><audio src="http://2ndbc.org/podcasts/2013.09.29.m4a" controls=""></audio>
<p><a href="http://2ndbc.org/podcasts/2013.09.29.m4a">Download this podcast.</a></p></div>
This works great in Internet Explorer 9 on Windows 7, Safari 6.x on OS X 10.8 and Chrome on OS X. I'm also told it works fine on the latest Chrome and Firefox on Windows 7. However, it doesn't seem to work with Firefox or Chrome on Windows XP. I don't have access to an Android phone, but I was also told by one person that it didn't work on Android. I've tried both M4A/AAC and MP3 files. (As far as I can tell, it should work now that Firefox can support MP3 files.)
I'm hoping I can come up with a solution that lets me avoid using a Flash-based player -- just to keep things simple, yet compatible with any current version browser.