I found the problem, though I don't think it should be a problem. I have a Line-6 Helix connected to my desktop via USB. If the audio output is set to the Helix when I start Pandora, I have the problem described in the top post. If I simply set the audio output to the desktop's sound device, Pandora will work normally. Then I can switch the audio output to the Line-6 Helix, and Pandora will continue to work normally. Pandora can't start properly when the audio output is set to Line-6 Helix over the USB. I suspect that Pandora has a problem with USB-connected audio devices.   ... View more