Hey there @GMarx,
Thanks for reaching out about this here in the Community.
First up, it's well worth running a clean reinstall to get rid of any cached files that might be causing trouble.
On another note, you can reduce the data usage by toggling on Data Saver from the app's settings on your mobile device. To find out how you can do this, along with other tips, we'd recommend taking a look at this support site article.
Lastly, keep in mind that the higher the stream quality, the more data will be used. We’d recommend checking the Stream quality in your app Settings.
Keep us posted on how it goes.
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