I have no idea when this changed, but the default behavior now in Canvas is that when you record an audio file from the main editor (You select no video in the settings/audio only) Canvas will generate html code for video. (Old audio clips copied in from an old course appear to be unaffected, only new recordings)
Default HTML Created (creates large video window when clicked)
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I'm not talking about the box that's created on a page, but when you actually click play you get a full size video window to play back the audio. I reported to tech support because in my mind this is a very annoying bug. I played around and discovered if you change the html in two places to "audio" it seems to be giving me the intended behavior. (small horizontal audio player) Just wanted to let anyone know how to fix temporarily until a permanent fix is in place.
Change "Video" to "Audio" in HTML to keep small audio player size
class="instructure_inline_media_comment audio_comment" data-media_comment_type="audio" data-alt=""></a><br /></span></span><span