[mythtv-users] Satix S2 Dual regular dropouts / poor signal quality?

[Robert Longbottom]

  Hi list,

I've just bought a Satix-S2 Dual to replace my existing HVR3000 and 
Technotrend S-1500.  I've set it up using the ngene driver from kernel 
2.6.35.4 and the firmware linked to from the linuxtv wiki 
(http://linuxtv.org/wiki/index.php/Mystique_SaTiX_S2_Dual).  My plan was 
to retire the 2 PCI cards for a single dual PCIe card to free up some 
space in my case (for other cards ;-) ).

However after just a days testing of the Satix card I've had numerous 
failed recordings and dropouts mid recording (where recording just 
stops).  Also livetv regularly freezes and kicks me back to the main menu.

I've turned on the "record" log option for the backend and it the log 
when a recording stops half way through it reports:

    2010-10-09 12:02:00.631 DevRdB(/dev/dvb/adapter103/frontend0) Error:
    Poll giving up
    2010-10-09 12:02:00.640 DevRdB(/dev/dvb/adapter103/frontend0):
    fill_ringbuffer: error state
    2010-10-09 12:02:00.648 DVBSH(/dev/dvb/adapter103/frontend0) Error:
    Device error detected
    2010-10-09 12:02:00.648 DVBSH(/dev/dvb/adapter103/frontend0):
    RunTS(): shutdown
    2010-10-09 12:02:00.648 PIDInfo(/dev/dvb/adapter103/frontend0):
    Closing filter for pid 0x0
    <snip>
    2010-10-09 12:02:00.660 DVBSH(/dev/dvb/adapter103/frontend0):
    RunTS(): end
    2010-10-09 12:02:00.701 DVBRec(1:/dev/dvb/adapter103/frontend0)
    Error: Stream handler died unexpectedly.

Googling around, this looks like it's a signal problem, so I kicked off 
'femon' against the dvb card.  It's reports values for Signal strength 
around 80%, SNR around 70%, UNC=0, BER is usually zero for one of the 
inputs and seems to be always 1 for the other input(?)  In comparison 
the HVR and the Technotrend report SNR values of >95%.  I'm using 
exactly the same two feeds from my dish into Satix as I have been for 
the past two years into the HVR and the Technotrend and in the past two 
years I don't think I've had a single failed recording due to a signal 
problem.

I'm also getting the following errors repeating quite a lot for the BBC 
channels in my logs, but that also happens with the old cards and it 
doesn't seem to matter there, so I'm guessing it isn't directly related 
to the problem:

    2010-10-09 21:10:38.219 DVBRec(8:/dev/dvb/adapter101/frontend0): PID
    0x138c discontinuity detected
    2010-10-09 21:10:38.250 DVBRec(8:/dev/dvb/adapter101/frontend0): PID
    0x13f0 discontinuity detected
    2010-10-09 21:10:38.709 DVBRec(8:/dev/dvb/adapter101/frontend0): PID
    0x138c discontinuity detected
    2010-10-09 21:10:38.753 DVBRec(8:/dev/dvb/adapter101/frontend0): PID
    0x13f0 discontinuity detected
    2010-10-09 21:10:39.238 DVBRec(8:/dev/dvb/adapter101/frontend0): PID
    0x138c discontinuity detected



So the questions are...

Is anyone else using the Satix S2 Dual successfully?  If so, what values 
do you get for SNR? (I don't believe there is anything wrong with my 
dish / cabling because it's been working fine with the other two cards 
for a long time now)  Is the Satix just not as good at picking up the 
signal?

According to a thread from back in April [1] there has been some 
success, but there was a lot of work pending on patches to the drivers.  
Does anyone know if these patches have made it into the kernel yet?  Or 
should I try switching to the linux-dvb drivers rather than using the 
in-kernel drivers?

Is there anything else I can do to work out why the signal seems to be 
so much worse on this card than on my other (old) cards?

I noticed on the digital devices site [2] there is what looks like a 
newer version of the firmware (ngene_17.fw).  I tried to use it, but it 
didn't work.  Presumably it's somehow tied to the driver version in the 
kernel?

How do I/can I fix the "discountinuity" errors?

Thanks!
Robert.

[1] http://www.mythtv.org/pipermail/mythtv-users/2010-April/286115.html
[2] http://www.digitaldevices.de/pageID_9262549.html

System Info:
mythtv-0.23.1_p25496 on Gentoo Linux, kernel version 2.6.35.4


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