I wanted to renew my yearly license but canceled it by accident instead. I quickly reinstalled it but noticed that all of my mp3 audio player instances have changed color and the player buttons have changed to unrecognizable icons. Some text was even mysteriously duplicated. I tried clearing my browser's cache but still, have the same problem. 

Pro Free is version 4.0 but the Pro add-on is version 3.6.

I just upgraded to the pro-add on 4.0 and it solved the problem. Thank you so much for your quick response!!