Comment 7 for bug 500822

built (k)ubuntu 10.04 live-usb with "usb startup disk creator (ubuntu 9.10)" and have same problem:

first:
(process: xxx): Glib-Warning ** getpwuid_r(): failed due to unknown user id(0)

then a lots of:
stdin: error0
/init: line 7: can't open /dev/sr0: No medium found

after a while:
opens ash and writes:
(initramfs)Unable to find a medium containing a live file system