cheers for the info.
as usual im trying to do it on the cheap though
my tv has a S/PDIF out, there is a sony DAV S800 5.1 system on ebay thats 5 mins down the road from me which has an S/PDIF input. would i be right in thinking i could just leave the PS3 connected to the tv via HDMI and connect the tv to surround sound via S/PDIF?