Why does my YouTube music app still use data when listening to downloaded music?

[nz0j]

I have a YouTube premium account and download music to my Galaxy S8 to listen to offline while travelling. I've noticed that the YouTube music app will use about 10 MB of mobile data per hour while listening to downloaded content away from WiFi. I have the app set to only stream on WiFi as well. I can download the same content in Google Play Music and have it use no data while listening offline. I'm just curious why one will use data and the other won't.

 

[ManiacJoe]

From your brief description, is sounds like the local files are getting ignored and streaming is used.

As a test, while Yahoo is playing the music, turn on Airplane mode and see if the music stops.

 

[nz0j]

From your brief description, is sounds like the local files are getting ignored and streaming is used.

As a test, while Yahoo is playing the music, turn on Airplane mode and see if the music stops.

The music still played while airplane mode was turned on. I would think if it was actually streaming the music I would see more than 10MB of data being used in an hour though.