How to Fix the App Unexpectedly Stopping when it's in the Background
If the app stops while it is in the background or the screen is off, the problem is the device's battery optimizer turning off what it thinks is an unused app.
The solution is simple, but depends on the device model. There is a dedicated site with detailed instructions on how to fix this on each device known to turn off background apps:
https://dontkillmyapp.com/
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Help, the Music is Pausing while in the App
If the app is on and the music pauses seemingly out of nowhere, it is a different issue, most likely caused by other apps interrupting audio. For a solution to this issue see here.Help, I can't get into the App, it closes when I try to open it
If the app closes when it is trying to open, the problem is a recent Google WebView update. See this article for the solution: https://musicspeedchanger.com/forum/discussion/339/google-webview-crashing-android-apps