I have figured out a work around (other than turning off the screen saver option).  Change the screen saver to not kick on for 5 or 10 minutes.  Under settings, theme, (under additional settings, choose screensaver start time), choose 5 or 10 minutes.  This will cause the Pandora screen saver to kick on before the ROKU screen saver and this will no longer be an issue. ... View more