After disabling C-States in the BIOS completely (if possible) you
have to know whether this is a driver or a TelliCast problem. You
should have Manu Abrahams famous demodulator driver module stv090x
with CrazyCat's special trick parameter ts_nosync (on) loaded.
You can check for continuity and TEI errors in module dvb_core
# echo 1 > /sys/module/dvb_core/parameters/dvb_demux_tscheck
should report these errors in the kernel log. After some
normal initial errors there should be none. Go back with
# echo 0 > /sys/module/dvb_core/parameters/dvb_demux_tscheck
The second culprit might be your hdd. If this is a NAS you
should not listen music and watch movies from the same hdd.
If possible use a dedicated fast SATA data hdd for TelliCast.
This disk should not fall asleep if TelliCast has some pause.
Tmp directories + channel data must be on the same partition.
P.S. I'v never had a NAS and cannot comment on your hardware.