You would need to make a small code tweak on file /components/com_muscol/models/playlists.php
You need to change the order in the MySQL query.

So, the query I need to change is:
$this->query = ' SELECT pl.*,us.name as user_name FROM #__muscol_playlists as pl '.
' LEFT JOIN #__users as us ON us.id = pl.user_id ' .
' WHERE pl.user_id = '.$this->user->id
;
by adding an "ORDER BY" .

What is the variable I need to use for the ordering? Can you please help me.

Thank you,

ORDER BY pl.id DESC

That did it! Thank you for your help.