Help with stuttering

hawk2k2 · **25th December 2006, 12:08 AM**

Tuner: DNTV! Hybrid LP

Specs:
3GHz Pentium 4 Northwood
1GB 4200 DDR RAM
320GB SATA NCQ Seagate (used for timeshift and recording)
9800pro (tv out via VGA)
sound blaster audigy DE
windows MCE 2005 rollup 2

TV: 40inch samsung lcd tv 1366x768 (no digital tuner)

Hello all,

I have been wanting a HTPC setup for awhile and now I actually have funds to set one up. I have had this equipment for about 3 weeks now and I cannot seem to set it all up properly and its starting to really bug me sad.gif

To start off with, I had a DVICO FusionHDTV Dual Digital 4, which I returned as I found it to have many problems. Then I bought a new DNTV card as listed above and these problems still arose sad.gif

Problem1: Stuttering. The picture seems to stutter on 9 and 10 SD and HD, but seems fine on 7 SD and HD (im located in perth, western australia). The severity of this changes. Sometimes it hardly happens, sometimes just the picture pauses and sound continues, sometimes the picture and sound stops for a split second, and sometimes it becomes unwatchable. I have tried many things to fix this including:

reducing pci latency
updated all drivers
updated windows mce
tried DNTV, nvidia, cyberlink and mpv codecs
tried MediaCenter, Mediaportal, DNTV!, "Digital TV"
tried enabling/disabling DXVA
tried 1360x768@60, 1024x768@75 (tv doesnt support 1360x768@50 nor 75)
disabled timeshifting
priority to high
PCI slots 2,3,4 (not 1 as 9800pro is blocking)

I am now out of ideas completely and its becoming very frustrating. Signal quality on all the stations is always above 78% for strength and 90% for quality.

Problem2: After the HTPC has been on overnight, it might not pick up stations in the morning. It comes up with "no signal" or whatever the same error message in any of the programs I have tried.

Any help would be very greatly appreciated. I kind of wish that I went for the set top box option now lol.

Cheers
Hawk

vlad · **25th December 2006, 05:50 AM**

Hi,
Two thing I would try:
1. Install different version of video drivers.
2. Try different video card
3. Try Avermedia or Hauppauge tuners.

hawk2k2 · **27th December 2006, 10:35 AM**

Thanks for your reply. It seems that I may have fixed the problem by uninstalling my antivirus. Looks like just adding exceptions wasnt enough.

Hawk

hawk2k2 · **28th December 2006, 12:18 AM**

no that didnt help

9 and 10HD are still stuttering... not too sure about their SD channels yet. 7HD is running perfectly after 3 hours watching it. Here is my log of scanchannelsbda-uk... could my problem be with reception?

Code:

-----------------------
ScanChannelsBDA-UK starting
Build - v2.4.3.0
Checking for new BDA DVB-T Cards
  Tuner - 3056 BDA DVBT Tuner
    @device:pnp:\\?\pci#ven_1131&dev_7133&subsys_00381822&rev_d1#4&2e98101c&0&60f0#{71985f48-1ca1-11d3-9cc8-00c04f7971e0}\{3ff44ee5-8547-402a-94f3-d447f4d70c00}
      Finding Demod and Capture filters
        Trying - 3056 BDA Digital Capture
          @device:pnp:\\?\pci#ven_1131&dev_7133&subsys_00381822&rev_d1#4&2e98101c&0&60f0#{fd0a5af4-b41d-11d2-9c95-00c04f7971e0}\{5bb3dbd0-9e1e-424c-9281-6b5e71090c00}
            SUCCESS
        Checking for Capture filter
          Trying - BDA Slip De-Framer
            @device:pnp:\\?\root#system#0000#{fd0a5af4-b41d-11d2-9c95-00c04f7971e0}\{03884cb6-e89a-4deb-b69e-8dc621686e6a}&global
          Trying - BDA MPE Filter
            @device:pnp:\\?\root#system#0000#{fd0a5af4-b41d-11d2-9c95-00c04f7971e0}\{8e60217d-a2ee-47f8-b0c5-0f44c55f66dc}&global
      Finished Finding Demod and Capture filters
      Capture - 3056 BDA Digital Capture
        @device:pnp:\\?\pci#ven_1131&dev_7133&subsys_00381822&rev_d1#4&2e98101c&0&60f0#{fd0a5af4-b41d-11d2-9c95-00c04f7971e0}\{5bb3dbd0-9e1e-424c-9281-6b5e71090c00}
Finished Checking for new BDA DVB-T Cards
Found BDA device: 3056 BDA DVBT Tuner
# signal locked = Y present = Y strength = 0 quality = 0


============================================================================

Frequency (Scanned) = 177500kHz
Frequency (Actual)  = 177500kHz

Transmitter Name    = Seven Network

Channel Name           LCN   SID    Vid   Aud   PMT
-------------------------------------------------------------------
7 Digital           ,    7, 1376, 1537,  1538, 1536    # Teletext=1540
7 Digital 1         ,   71, 1377, 1537,  1538, 1552    # Teletext=1540
7 Digital 2         ,   72, 1378, 1537,  1538, 1568    # Teletext=1540
7 Digital 3         ,   73, 1379, 1537,  1538, 1584    # Teletext=1540
7 HD Digital        ,   70, 1380, 1601, A1603, 1600    # Teletext=1540
7 Program Guide     ,   77, 1382, 1633,  1634, 1632    #


# locked = Y, present = Y, strength = 50, quality = 95%
# locked = Y, present = Y, strength = 50, quality = 95%
# locked = Y, present = Y, strength = 50, quality = 95%
# locked = Y, present = Y, strength = 50, quality = 95%
# locked = Y, present = Y, strength = 50, quality = 95%
# locked = Y, present = Y, strength = 50, quality = 95%
# locked = Y, present = Y, strength = 50, quality = 95%
# locked = Y, present = Y, strength = 50, quality = 95%
# locked = Y, present = Y, strength = 50, quality = 95%
# locked = Y, present = Y, strength = 50, quality = 95%

# Average quality on 177500kHz = 95%

============================================================================

Frequency (Scanned) = 191625kHz
Frequency (Actual)  = 191625kHz

Transmitter Name    = Nine Network

Channel Name           LCN   SID    Vid   Aud   PMT
-------------------------------------------------------------------
Nine Digital        ,    9, 1025,  512,   650,  256    # Teletext=576
Nine Digital AC3    ,     , 1025,  512,  A651,  256    #
Nine HD             ,   90, 1030,  522,  A750,  261    # Teletext=576


# locked = Y, present = Y, strength = 50, quality = 95%
# locked = Y, present = Y, strength = 50, quality = 95%
# locked = Y, present = Y, strength = 50, quality = 95%
# locked = Y, present = Y, strength = 50, quality = 95%
# locked = Y, present = Y, strength = 50, quality = 95%
# locked = Y, present = Y, strength = 50, quality = 95%
# locked = Y, present = Y, strength = 50, quality = 95%
# locked = Y, present = Y, strength = 50, quality = 95%
# locked = Y, present = Y, strength = 50, quality = 95%
# locked = Y, present = Y, strength = 50, quality = 95%

# Average quality on 191625kHz = 95%

============================================================================

Frequency (Scanned) = 219500kHz
Frequency (Actual)  = 219500kHz

Transmitter Name    = Network TEN
#Alternate frequency
#Network_3("Network TEN", 788500, 7, 1)


Channel Name           LCN   SID    Vid   Aud   PMT
-------------------------------------------------------------------
TEN Digital         ,    1, 1665,  512,   650,  257    # Teletext=576
TEN Digital AC3     ,     , 1665,  512,  A651,  257    #
TEN Digital         ,   10, 1669,  512,   650,  256    # Teletext=576
TEN Digital AC3     ,     , 1669,  512,  A651,  256    #
TEN Guide           ,   11, 1671,  513,   660,  262    #
TEN HD              ,   12, 1672,  514,  A672,  263    # Teletext=577
TEN Guide           ,  100, 1673,  513,   660,  264    #


# locked = Y, present = Y, strength = 55, quality = 95%
# locked = Y, present = Y, strength = 55, quality = 95%
# locked = Y, present = Y, strength = 55, quality = 95%
# locked = Y, present = Y, strength = 55, quality = 95%
# locked = Y, present = Y, strength = 55, quality = 95%
# locked = Y, present = Y, strength = 55, quality = 95%
# locked = Y, present = Y, strength = 55, quality = 95%
# locked = Y, present = Y, strength = 55, quality = 95%
# locked = Y, present = Y, strength = 55, quality = 95%
# locked = Y, present = Y, strength = 55, quality = 95%

# Average quality on 219500kHz = 95%

============================================================================

Frequency (Scanned) = 226500kHz
Frequency (Actual)  = 226500kHz

Transmitter Name    = ABC Perth

Channel Name           LCN   SID    Vid   Aud   PMT
-------------------------------------------------------------------
ABC HDTV            ,   20,  736,  516,  A654,  258    # Teletext=580
ABC TV Perth        ,    2,  737,  512,   650,  256    # Teletext=576
ABC TV Perth AC3    ,     ,  737,  512,  A660,  256    #
ABC2                ,   21,  738,  513,   651,  257    # Teletext=577
ABC TV              ,   22,  739,  512,   650,  259    # Teletext=576
ABC DiG Radio       ,  200,  742,    0,   690,  261    #
ABC DiG Jazz        ,  201,  743,    0,   700,  262    #


# locked = Y, present = Y, strength = 60, quality = 95%
# locked = Y, present = Y, strength = 60, quality = 95%
# locked = Y, present = Y, strength = 60, quality = 95%
# locked = Y, present = Y, strength = 60, quality = 95%
# locked = Y, present = Y, strength = 60, quality = 95%
# locked = Y, present = Y, strength = 60, quality = 95%
# locked = Y, present = Y, strength = 60, quality = 95%
# locked = Y, present = Y, strength = 60, quality = 95%
# locked = Y, present = Y, strength = 60, quality = 95%
# locked = Y, present = Y, strength = 60, quality = 95%

# Average quality on 226500kHz = 95%

============================================================================

Frequency (Scanned) = 536625kHz
Frequency (Actual)  = 536625kHz

Transmitter Name    = SBS NETWORK

Channel Name           LCN   SID    Vid   Aud   PMT
-------------------------------------------------------------------
SBS HD              ,   30,  800,  102,   103, 1024    #
SBS DIGITAL 1       ,    3,  801,  161,    81, 1025    # Teletext=41
SBS DIGITAL 2       ,   33,  802,  162,    83, 1026    #
SBS EPG             ,   31,  803,  163,    85, 1032    #
SBS RADIO 1         ,   38,  814,    0,   201, 1027    #
SBS RADIO 2         ,   39,  815,    0,   202, 1028    #


# locked = Y, present = Y, strength = 55, quality = 95%
# locked = Y, present = Y, strength = 55, quality = 95%
# locked = Y, present = Y, strength = 55, quality = 95%
# locked = Y, present = Y, strength = 55, quality = 95%
# locked = Y, present = Y, strength = 55, quality = 95%
# locked = Y, present = Y, strength = 55, quality = 95%
# locked = Y, present = Y, strength = 55, quality = 95%
# locked = Y, present = Y, strength = 55, quality = 95%
# locked = Y, present = Y, strength = 55, quality = 95%
# locked = Y, present = Y, strength = 55, quality = 95%

# Average quality on 536625kHz = 95%

============================================================================

Regards
Hawk

logifuse · **28th December 2006, 08:50 AM**

Quote:

Originally Posted by hawk2k2

... could my problem be with reception?

# locked = Y, present = Y, strength = 50, quality = 95%
# locked = Y, present = Y, strength = 50, quality = 95%
# locked = Y, present = Y, strength = 55, quality = 95%
# locked = Y, present = Y, strength = 60, quality = 95%
# locked = Y, present = Y, strength = 55, quality = 95%

Looks like it.

95% quality is fine, but with the signal strength that low, it means that you have no head room when it comes to the signal strength. Any dip (it's not a perfectly linear thing) & the signal is gone. You really need 66% or better for reasonably consistent reception.

What's your antenna system like & how are you located in realtion to the towers (line of sight, distance, etc)? How much is the signal split from the antenna? If the antenna cable runs directly to your card without any other outlets (unlikely), then a masthead amplifier probably won't help you (unless it's a really long cable run from the antenna). If it's split more than once, a mast head amp might help. I wouldn't get too hung up over poor cabling as that's more likely to be affected by interference noise & shouldn't impact signal strength much (possible, but unlikely).

Justin

hawk2k2 · **28th December 2006, 09:28 AM**

Thanks for your reply logifuse.

I did notice that this program outputted different results compared with the DNTV Live! software. The DNTV software reported 80-85% strength and 95% quality for 7HD, and 75-80% strength and 90-95% quality for 10HD from memory.

I am unsure how the antenna is setup. It has been installed for about 15years, and about 7 years ago we got another output installed, so there are two outputs currently. The cable run is not long (well it shouldnt be) as its around approximatly 10m away from the antenna for the HTPC, and 20m from other outlet.

logifuse · **28th December 2006, 11:01 AM**

Quote:

Originally Posted by hawk2k2

Thanks for your reply logifuse.

I did notice that this program outputted different results compared with the DNTV Live! software. The DNTV software reported 80-85% strength and 95% quality for 7HD, and 75-80% strength and 90-95% quality for 10HD from memory.

I am unsure how the antenna is setup. It has been installed for about 15years, and about 7 years ago we got another output installed, so there are two outputs currently. The cable run is not long (well it shouldnt be) as its around approximatly 10m away from the antenna for the HTPC, and 20m from other outlet.

The DNTV results seem more realistic, particularly seeing as you don't have trouble with 7. Which version of ScanchannelsBDA did you use? There's the one in the downloads section, but there's also a parallel version http://nate.dynalias.net/ScanChannel...annelsBDA.html - maybe try the one you didn't use & see what results that gives.

I know 90-95% quality sounds like it should be fine, but it probably isn't. The signal is transmitted using a process called forward error correction (FEC) where a percentage of the transmission bandwidth is sacrificed to allow for a sort of buffering of the signal using that sacrificed bandwidth. If quality of the signal you receive drops by the amount of FEC or more, you get signal drop-outs.

This is a very simplified view of how FEC works, but basically, if 6% of the signal (for the sake of the argument, let's call the total signal 106%) is used for FEC (& I'm not sure what it is, but that's probably roughly the amount) & your quality is at 95%, you'll be OK as there is enough FEC to cope (filling the missing 5% with that 6% available). If your quality is 93%, you're in trouble as you're trying to fill that 7% gap with 6%.

Also, remember that the different channels for each station (SD, HD, Program Guide, etc) are all the same signal, so any variation in viewing of them isn't signal, but it more likely to be decoder or hardware limitations.

Justin

hawk2k2 · **28th December 2006, 12:26 PM**

Ok thank you so much I am starting to understand it now.

When I get home I will see what version of the scanner I was using and try the other. I will also try and watch the SD channels and see how they go.

edit: By the way, I have also got my hands on some 720p and 1080i sources and they run fine in media player with no jerkyness or stuttering at all.

Cheers
Hawk

Mysteron · **28th December 2006, 06:11 PM**

MCE does seem to be very picky when it comes to signal strength so I'd be looking at getting a signal booster first up (Dick Smith sell good ones at reasonable prices) and if that does not help then looking at a new antenna system including good quality RG6 cable, F-type connectors and good flyleads from wall connector to MCE PC.
On another tack some motherboards (usually non intel chipsets such as SIS and VIA) were not happy with SATA drives and could cause stutter, this occurred with my first MCE build and getting an IDE drive solved it.
Good luck.

scott_mckenzie · **29th December 2006, 08:53 AM**

Hi,

I have a Twinhan tuner and found similar problems... Once my aerial was replaced though 100% prefect! Best advice I can give you is to borrow a tuner off someone for 2-3 days to determine if the reception is the problem (easiest if you have a mate with a USB one). I found that my issue was intermittent as well so I'm pretty sure that's where your issue is.

Gook Luck!

Scott