Comment 7 for bug 446575

tuukka your problem was simple that you haven't the firmware file installed
in karmic the firmware files was splitted into 2 packages: linux-firmware installed by default with free firmwares and linux-firmware-nonfree not installed by default with non-free firmwares

to can watch dvb with many tv-cards we must install the linux-firmware-nonfree package or try to get the firmware and install like you read in the ubuntuforums