As ashrodan mentioned: the Garmin Forerunners do this. What they didn't mention is that you can also attach it to a Mac or PC via USB and copy over your own mu

As ashrodan mentioned: the Garmin Forerunners do this. What they didn't mention is that you can also attach it to a Mac or PC via USB and copy over your own music to it. IIRC (but it's been a while) there are also tools to do this on Linux in the repos. https://www.garmin.com/en-US/blog/general/which-garmin-smartwatches-have-music-storage/ https://www.garmin.com/en-US/blog/general/which-garmin-smart... And... Page 47 of https://www8.garmin.com/manuals/webhelp/forerunner245/EN-US/Forerunner_245_OM_EN-US.pdf https://www8.garmin.com/manuals/webhelp/forerunner245/EN-US/... as an example.