Installing from USB CD-drive

[Josef Wolf]

hello,

When installing the alternate cd from an USB-CDROM (e.g. on a netbook),
I get the error that no CDROM could be found. Then I am thrown into the
d-i main menu. On retry, the cdrom is found, and the installation proceeds
seamlessly.

While it's not a big deal, it is boring when the install should go without
any interactions (preseeded)

Any idea what causes detection of the usb CD to fail and how to fix that?