I've had the same problem since upgrading to Android11. Poweramp just will NOT work.
I reached out to support, uploaded logs... Got nowhere. They didn't even reply.
If I hit the + in Music Folders Selection I get "Add Storage/Provider Plugin Please use sidebar in the system dialog to select the target storage/provider plugin"
Then I get a "Failed The folder selection system component seems to be missing/disabled/frozen on your device. Please enable the component. Alternatively, you can enable legacy mode. The file access legacy mode won't be supported in the future versions of Android" then a quick popup "No Activity found to handle Intent { act=android.intent.action.OPEN_DOCUMENT_TREE(has extras) }"
I've made sure Poweramp has All Files and media access permission. I tried enabling file access legacy mode, which worked! Until either I reboot my phone or quit/restart Poweramp. I've also cleared storage/cache of the app and uninstalled/reinstalled.
Version build-911-arm64-play
Oneplus 7t pro 5g mclaren on Android 11
Google Files app is installed and can browse storage. Music is stored in internal storage/Music
full purchased
EDIT: Sorry. Didn't mean to hijack this thread. This is the first time I've read about someone with similar problems.