I am also having this issue, with the Windows Desktop App (v15.0.3.0). Just started a few days ago. I get this message after every song, and every time I press the next button to skip a song. It takes several seconds to sometimes a few minutes before it is able to play the next song. I also get this message trying to navigate from the "Now Playing" screen into my app settings with similar behavior - it takes several seconds to sometimes a few minutes before the settings screen opens. I've tried resetting the app, downgrading my streaming quality settings, restarting the app, my computer and my router. After resetting the app, it will immediately play one song, then right back to this behavior. Pandora works just fine on my network on other devices, and I have no other network issues on this same computer.
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