Adam,
Thanks for this info, I had just found it. It find it a bit strange that a user must do searches in forums and help files in order to change a moderately important setting like that. Maybe you can submit a feature request that it be added within the application, so a user doesn't have to waste time and spin their wheels and feel irritated about it, like I did.
OhSindeOne, I found an instruction that should stop the auto start:
To do that on Windows:
Right-click the Start button.
Select Task Manager.
Click the Startup tab. (If you don't see the Startup tab, select More details.)
Select Pandora.
Select Disable.
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