Problem resolved... maybe... I hope.
I had an idea that something in the -500 got hosed somehow so I decided to change over to my external eSATA drive before retiring last night. That would allow the spool to update the SW on the eSATA to the new 59e rev.
Woke up this AM and Pandora is working perfectly on the -500. Pandora asked to be activated, which I expected, and it played fine.
Shut everything down and changed back to the internal HD and Pandora is working perfectly on the -500. Didn't need to be activated and 59e was already on the internal drive from before.
So, that ruled out the hard drive or software on it as the problem.
It did seem to me that the -500 somehow hosed it's connection to Pandora and that connection could not be cleared or reset without actually running the Pandora app which the -500 would not let me do. That's why clicking the Pandora icon dropped back to the extras
screen. Perhaps changing HDs forced a reset of those links and resolved the problem.
Don't know whether that procedure resolved the problem, escalating the problem at DTV resulted in a fix from engineering, or it just healed itself... and I don't care.
Edited by subeluvr, 11 February 2012 - 12:26 PM.