It seems nearly anything can make rhythmbox crash, I've always found it buggy.
This crash seems to be something related to ecryptfs but it's hard to say. After re-opening rhythmbox so it sits in the Gnome panel/tray, and letting it load/find all of my songs let's it work again. If I show it too soon (I wait 10-15 minutes for everything to scan first) then it will crash over and over.
[171938.995645] ecryptfs_read_and_validate_header_region: Error........