A long time ago, I heard you can pass by any PCI device through Xen. You only have to identify your PCI device (
lspci -vn I guess).
Anyway, in the meantime I bought an Vantage DVB-S receiver and don't use MediaPortal anymore
. Of course, I regularly miss MediaPortal. By now I have not ever tried Xen virtualisation. Kind regards and good luck!