When I upgrade AllVideos from version 4.7.0 to 4.8.0 on my Joomla! 3.8.1 site, the MP3 player does not display properly. All I see is a black box. If I set the height high enough the black box will show a gray triangle "play" icon. Clicking the icon does play the audio. I found a posting that seemed to describe the same issue (www.joomlaworks.net/forum/allvideos/47876-no-player-for-local-audio-files) but that fix did not solve the problem.

Any thoughts on how to fix the issue?

Thanks

Inspect the black box with your browzer tools and see the filename it is pointing to.
Is the filename there correct? If not change it in the tag and this may get it playing.
Formatting later after it plays

The file does play, but the controls are unavailable and the site visitors won't know that it's an MP3 player.

Formatting later after it plays

Now its time to look at the plugin audio player settings and use the inspection tool to check the css to see what makes it do what you want it to
Also, searching the forum for format audio player may yeild answers
If you have a link to the site please post it

Hmmm... Its working now. I'm not sure if there was some kind of caching issue or if an update to another component cleared up the issue. I'm hesitant to upgrade my production site until I can figure out what happened. I'll do some more testing.

Thanks.

Keep an eye on your browser developer tools' console tab.
JavaScript errors can break several components.

Hello Krikor, I have exactly the same issue than Christopher. As Christopher solved it without giving a solution, can you help me and we shall give the right answer in this topic, thank you.
All was right one month ago with Joomla and this extension and since I made Joomla 3.8.x update the bug happened.
Here is the page with a problem : www.gerda-hartman.net/carriere-artistique/extraits-audio
enjoy !

Do you by any chance use posters for these tracks?

Hello Krikor,
I'm not sure to understand what you means with 'Posters".
If it is recorded pictures linked to recorded sound traks, the answer is No.
and the sound tracks has been provided by the artist herself.
Thank you to care with this issue

For the record, I'm still having issues on my site. I haven't had much time to work on this, but I was not able to replicate the fix that appeared on it's own. I hope to devote some time to troubleshoot this in a couple of weeks. I hope to provide some useful information fairly soon.