[mythtv-users] HD-3000 recording corruption

[Craig Partin]

> > > > >>>>This is the first time I have been stumped in over two years of
> > > > >>>>mythtv
> > > > >>>>use.  I got my HD-3000 working just fine tuning QAM stations over
> > > > >>>>cable in myth.  The system works flawlessly and reliably except
> that
> > > > >>>>QAM recordings get trashed when anything else is happening on the
> > > > >>>>system.  It records beautifully when nothing else is happening.
> This
> > > > >>>>happens on all channels, HD and SD.  I can playback 1080i content
> > > > >>>>with
> > > > >>>>XVMC just fine, even with bob.
> > > > >
> > > > >
> > > > > Sounds like interference getting into the HD-3000 from the video
> card.
> > > > > Try moving them farther apart, electrically shielding the card(s),
> and
> > > > > make sure if you have a jumper cable between the sound card and the
> HD-3000
> > > > > that it is either removed or has RFI protection (a couple of turns
> through
> > > > > a torroidal core at each end).
> > > > >
> > > > > Good Luck.
> > > > This was going to be my response too.
> > > > Since it is video related it has to be something the video card does,
> > > > either as an interference transmission or on the bus. Since it seems
> to
> > > > be size related I would not think it would be the bus. It is related
> to
> > > > the 'active' area of the screen.
> > > >
> > > > You might, just to see if that is what is going on, try putting
> > > > something between the 2 cards to shield them from each other. A piece
> of
> > > > aluminum plate, wrapped in cling wrap to avoid shorting things, would
> > > > do. Or for that matter a piece of alum foil between 2 sheets of paper.
> > > > Just remember to ground one corner of the shield to the case.
> > > >
> > > > Geoff
> > >
> > >
> > > My mobo has a communications PCI slot, and I put the HD-3000 there.
> > > It also has spread spectrum controls to reduce RFI.  I have switched
> > > slots and and toggled the RFI settings and noticed no change.
> > >
> > > I haven't done the exact test with the video card and signal strength
> > > but I cannot watch live TV or azap tune and watch in mplayer without
> > > corruption.
> > >
> >
> > Watching Live tv from the HD-3000 and with mythcommflag running in the
> > background gives an iowait of ~2.0%.  Nothing else in top looks bad
> > nor out of the ordinary.   I don't think this is bus traffic problems.
> > I'll break out the tinfoil this weekend and if shielding the card
> > doesn't work maybe I can make a nice hat.
> >
>
>
> I would first make sure there is no IRQ conflict, say between HD-3000 and
> the sound card.  I used to have similar problems.  After I change the PCI
> slots around the problem is gone.  I honestly don't think RF interference is
> a big issue here.
>
> DS


cat /proc/interrupts
           CPU0
  0:  203863193    IO-APIC-edge  timer
  1:        196    IO-APIC-edge  i8042
  4:     698510    IO-APIC-edge  lirc_serial
  9:          0   IO-APIC-level  acpi
 14:    9350847    IO-APIC-edge  ide0
 15:     724311    IO-APIC-edge  ide1
 16:  285510998   IO-APIC-level  ehci_hcd:usb1, eth0
 17:    5920779   IO-APIC-level  NVidia CK8
 18:   10490633   IO-APIC-level  libata
 19:   64216503   IO-APIC-level  nvidia
 20:    8995727   IO-APIC-level  ivtv0
 21:    3575985   IO-APIC-level  cx88[0], cx88[0]
NMI:          0
LOC:  203871752
ERR:          0
MIS:          0


Should be OK.  There are no usb devices and I haven't noticed any
network issues.