Hello @WayneD79 and welcome to the Community. There is no way to store personal music on a Sense. Your Sense has a generic Music Control app and it lets you control any music app playing on your phone. Please see this expanded section of Fitbit's Help article for details. This should work for YouTube music playing on your phone.
Laurie | Maryland
Sense 2, Luxe, Aria 2 | iOS | Mac OS
Take a look at the Fitbit help site for further assistance and information.
Fitbit Product Experts Alumni are retired members of the Fitbit Product Expert Program. Learn more
Hi @WayneD79 - the advantage of using the built-in Music controls is you don't have to install anything and it will control any music playing on the phone.
In addition as it is a system function you don't have to stop what you are using on the watch to operate music and can even change volume.
Author | ch, passion for improvement.
Fitbit Product Experts Alumni are retired members of the Fitbit Product Expert Program. Learn more