i have struggled with this problem for months now. it has been the only reason i ever boot to windows, but finally after gathering data and advice from various sources i got it working under ubuntu 7.10. see attachment
This is how i did it:
1. install libqt4-dev, libusb-dev and build-essential in synaptic package manager
2. download and extract source code from http://www.andrewdsmith.plus.com/hummy/
3. Open terminal and navigate to the extracted humax directory.
4. Run "qmake-qt4 humaxGui.pro" ( ubuntu 7.10)
5. Run "make".
6. Run sudo /wherever the humax folder is/humax/humaxGui to open software as root
7. Connect USB cable between PC and PVR.
8. click connect on software
9. hopefully your all done
I am by no means an expert at linux or the command shell. I have spent months trawling various forums to get this working. all i have done is listed the steps i took. if these do not work for you then sorry i probably cannot help,