have u try to watch this chanels with the vlc player? of curse for the hdtv canel u will nead a strong pc, a good grafhic card and 1 giga ram and a strong cpu.
my recomndeiton is to invest in the new dvbs pc cards that supot both in mpeg2/4 and in a good pc, p4 qoudcore and a lot of ram and a huge hdd
and a good grafhicl card
hope i helped