First of all, I would like to thank the members of these forums for the invaluable information they have provided, without this forum I wouldn't have even known it was possible. Thanks especially to Rusty Gonad who seems to have a good handle on all of this.
I ordered an Infinity USB smart some time ago as they had a special and i intended to get sky eventually.
After researching the forums and googling extensively, I downloaded the following software:
DVBLink TVSource v2.01
Windows 7 Home Premium (ok i bought this one..)
I got sky installed and asked for an NZ45xx card (installer was indifferent)
This setup worked but i was getting glitches every 6 seconds, I determined that this was due to the Card ECM taking 2-3 seconds.
At this point I was pretty much resigned to purchasing a Jaycar reader and ditching the Infinity as i hadn't read anything good about the Infinity's, but I did a bit more googleing nonetheless and found this..
It turns out that there are two modes of using the Smart, one uses a windows program to create a virtual com port, this was how I had things running initially. But it is also possible to load a secondary firmware module on board, in this mode the windows software is not required, only drivers, and it sets up a different virtual com port which can be configured visa device manager.
After installing this module and setting the latency to 1ms, I re launched media centre and no more glitches! I have noticed that the Card ECM tim eis down to 0.36 seconds which i guess is the key.
Not sure if this will work with the Infinity USB unlimited, but tbh when the Smart is cheaper I don't know why you would bother..
Also, I am sure that other versions of the software I have used would work I downloaded several versions of NewCS and preferred 1.5 because the Card ECM times were lower than for 1.65.
Also, note that I have only had this running for ~1hr so far so there's plenty of time for it all to go pear shaped.
The picture is 1000x better than through the Pace box over 576i component. Shame it's not possible to get the HD ticket without an HDi box, because I don't think the HTPC would be worth it with an HDi sitting there..