Hi
The icon at the left of the title is always the player your music files are associated with on your PC.
All music files on my PC have a Green Dot, which is the icon for QCD player. When I click on a file, it will always open in QCD.
All that has happened is that your files have been associated with another player, it could be Windows Media Player for you at the moment.
All you need to do is change the association to another player.
In Window Explorer, right-click a music file and select 'Open with'. A small window will open showing all the programmes on your PC. You can then scroll to the player of your choice and select it. Also check the box to have all files of this type open with that player.
This option is available for all different files to be associated with your preferred application. For instance, I have all jpg files associated with my browser, so I don't have to launch a graphics prog to look at them
Cheers