[jameson_uk]

When watching DVB-T I am getting a little stutter in video evey so often and is annoying.

I have just switched from a 32" LCD connected up at 1360x768@60Hz via VGA to my new 42" Plasms connected up at 1920x1080@50Hz via HDMI.

This appears to have solved some of the issues which I guess were due to playing back 50Hz material at 60Hz?

There are still a few stutters left though and I could do with some help to identify their cause. TV signal appears ok, there is very little PC activity going on (minimal build with most non-essential things disabled).

Using a Pinnacle 7010ix TV card which is on the pci-express but so should be no interference with anything on the pci-bus. Graphics are via onboard Gefore 9400 IGP.

Any ideas on anything I can do to reduce / get rid of the stutter?

[cdldt]

It's probable that if they're intermittent with no regular pattern, they're due to impulse noise getting in at your aerial, or being picked up by the coaxial cable or connectors, rather than something specific to your PC.

[jameson_uk]

Originally Posted by cdldt

It's probable that if they're intermittent with no regular pattern, they're due to impulse noise getting in at your aerial, or being picked up by the coaxial cable or connectors, rather than something specific to your PC.

But not getting it on TV when using exactly the same cable. That said it is far noisier down by the PC.. guess I will have to get some better shielded cable then?

[shawnliu]

Originally Posted by jameson_uk

But not getting it on TV when using exactly the same cable. That said it is far noisier down by the PC.. guess I will have to get some better shielded cable then?

What the frame rate of your video source? Because you are using 50HZ signal to input to your TV, so if the frame rate of the video source is not 25 or 50, you must get a stutter.

[jameson_uk]

Originally Posted by shawnliu

What the frame rate of your video source? Because you are using 50HZ signal to input to your TV, so if the frame rate of the video source is not 25 or 50, you must get a stutter.

This on with PAL DVB-T (freeview) so is 50Hz.

[shawnliu]

Originally Posted by jameson_uk

This on with PAL DVB-T (freeview) so is 50Hz.

Sorry，confused. you conncet DVB-T to your PC, and PC to TV? Or?

[Rob100]

What software (DVB Viewer for example) do use use?

What MPEG2 decoder and is the decoder using DXVA and using hardware de-interlacing and acceleration on the GPU (IGP?).

[Count de Monet]

Originally Posted by jameson_uk

When watching DVB-T I am getting a little stutter in video evey so often and is annoying.

I have just switched from a 32" LCD connected up at 1360x768@60Hz via VGA to my new 42" Plasms connected up at 1920x1080@50Hz via HDMI.

This appears to have solved some of the issues which I guess were due to playing back 50Hz material at 60Hz?

There are still a few stutters left though and I could do with some help to identify their cause. TV signal appears ok, there is very little PC activity going on (minimal build with most non-essential things disabled).

Using a Pinnacle 7010ix TV card which is on the pci-express but so should be no interference with anything on the pci-bus. Graphics are via onboard Gefore 9400 IGP.

Any ideas on anything I can do to reduce / get rid of the stutter?

I'm having the same problem:

Starting here: http://www.avforums.com/forums/home-...ml#post8806950

[cdldt]

Download the DPC Latency Checker:
DPC Latency Checker
My MSI board had a BIOS bug which resulted in ridiculously high DPC latencies (>60000μs) at regular intervals. These correlated with brief stuttering of video playback. But, in my case it was nothing more than dropped frames - not full on blocking.

[Stephen Neal]

I have a 9400-based motherboard feeding 1920x1080/50Hz to my 40W4000 TV, and a Pinnacle 7010ix. I've not noticed any stuttering. I have 4Gb of RAM, Win 7 32 bit Beta 7000 (previously Vista SP1 32 bit), and an E7300 CPU.

It isn't my main TV viewing source - but when I've used it it has been fine.

Does the stuttering occur at the same place in recordings as when watching live through the same tuner (to force this record two DVB-T signals simultaneously and watch one of them live)? If that is the case then it is likely to be related to the path of the TV signal to Media Center (i.e. the signal quality, the card sensitivity, the connectivity between the card and the PC etc.) If the stutters are in different places in Live and Recordings of the same content then it is possble that the stutters are to do with the video replay system (video drivers, DXVA acceleration etc.) rather than the recording?

[Count de Monet]

Originally Posted by Stephen Neal

I have a 9400-based motherboard feeding 1920x1080/50Hz to my 40W4000 TV, and a Pinnacle 7010ix. I've not noticed any stuttering. I have 4Gb of RAM, Win 7 32 bit Beta 7000 (previously Vista SP1 32 bit), and an E7300 CPU.

It isn't my main TV viewing source - but when I've used it it has been fine.

Does the stuttering occur at the same place in recordings as when watching live through the same tuner (to force this record two DVB-T signals simultaneously and watch one of them live)? If that is the case then it is likely to be related to the path of the TV signal to Media Center (i.e. the signal quality, the card sensitivity, the connectivity between the card and the PC etc.) If the stutters are in different places in Live and Recordings of the same content then it is possble that the stutters are to do with the video replay system (video drivers, DXVA acceleration etc.) rather than the recording?

I have done what you suggest. I watched and recorded a show at the same time and noted down when the stutter/break-up's occur. I then played back the recording and the problem happens at exactly the same moment in time as it was happening when I was watching live. It seems to me that this is signal borne but I cannot understand why it does NOT happen on ANY other TV's attached to the same antenna.

My configuration at the moment is:

One short cable comes from the wall outlet to a 'Y' splitter that is fitted to the input of the TV card. From the other side of the 'Y' splitter another short cable feeds a small amplifier which in turn feeds three further outlets in the house. TV's connected to these outlets do NOT suffer from the stutter/break-up problem.

I'm still confused

[Count de Monet]

Originally Posted by cdldt

Download the DPC Latency Checker:
DPC Latency Checker
My MSI board had a BIOS bug which resulted in ridiculously high DPC latencies (>60000μs) at regular intervals. These correlated with brief stuttering of video playback. But, in my case it was nothing more than dropped frames - not full on blocking.

Thanks for the suggestion.

Using the software I have established that I do NOT have any latency problems which could affect recorded or live TV viewing.

[jameson_uk]

Originally Posted by shawnliu

Sorry，confused. you conncet DVB-T to your PC, and PC to TV? Or?

Ummm did miss a few important details out... DVB-T is connected to Pinnacle 7010ix and played back via MediaPortal and Nvidia MPEG2 codec.

After a little bit of playing I am fairly sure it is just interference on the aerial cable and not the PC. Getting some better cable on Monday so will be able to test then.

[Count de Monet]

Originally Posted by jameson_uk

Ummm did miss a few important details out... DVB-T is connected to Pinnacle 7010ix and played back via MediaPortal and Nvidia MPEG2 codec.

After a little bit of playing I am fairly sure it is just interference on the aerial cable and not the PC. Getting some better cable on Monday so will be able to test then.

Have you tried a regular Freeview TV on the same cable? and does your interference happen at regular intervals?

[MikeK]

Which channels is it doing it on?

There are 6 multiplexes on UK Freeview - 1,2,A,B,C,D!
Muxes 2 & A are using 64QAM, while all the others are using 16QAM - 64QAM allows more channels per multiplex, but is known to be quite a bit more susceptible to interference and signal/noise ratio etc.

Some receivers are better than others too - we used to have a Thomson PVR which was fine with channels on the 16QAM muxes, but those on the 64QAM muxes were constantly breaking up and freezing momentarily!
Swapped it out for a Digihome cheapie from Argos, and that's been fine on all channels!

Also, depending on where you are in the UK, the 6 muxes may not be transmitted at the same power. For instance, from Winter Hill, apparently 5 of the muxes are transmitted at 10kW, while one is 5kW (mux A apparently, which is a 64QAM mux too).

[Count de Monet]

Originally Posted by MikeK

Which channels is it doing it on?

There are 6 multiplexes on UK Freeview - 1,2,A,B,C,D!
Muxes 2 & A are using 64QAM, while all the others are using 16QAM - 64QAM allows more channels per multiplex, but is known to be quite a bit more susceptible to interference and signal/noise ratio etc.

Some receivers are better than others too - we used to have a Thomson PVR which was fine with channels on the 16QAM muxes, but those on the 64QAM muxes were constantly breaking up and freezing momentarily!
Swapped it out for a Digihome cheapie from Argos, and that's been fine on all channels!

Also, depending on where you are in the UK, the 6 muxes may not be transmitted at the same power. For instance, from Winter Hill, apparently 5 of the muxes are transmitted at 10kW, while one is 5kW (mux A apparently, which is a 64QAM mux too).

My problem happens in the most part on channels that I tend to think of as secondary channels like Virgin 1, Dave, ITV 2 + 1, CH4 ETC but very rarely on BBC1, BBC2, & ITV.

I live in Belper in Derbyshire surrounded by hills. The only transmitter that I can receive Freeview on is Sutton Coldfield.

Before I updated my HTPC I had two Black Gold GDI2510 single freeview tuners and never had any reception problems. From what I have read my present Black Gold BGT3540 is said to be a better tuner????

Do you think reception will improve after the full digital changeover?

EDIT:

My other concern is my interference happens at EXACTLY the same time within a 60 second time period. Better explained here: http://thegreenbutton.com/forums/thread/334682.aspx

[MikeK]

Originally Posted by Count de Monet

My problem happens in the most part on channels that I tend to think of as secondary channels like Virgin 1, Dave, ITV 2 + 1, CH4 ETC but very rarely on BBC1, BBC2, & ITV.

I live in Belper in Derbyshire surrounded by hills. The only transmitter that I can receive Freeview on is Sutton Coldfield.

Before I updated my HTPC I had two Black Gold GDI2510 single freeview tuners and never had any reception problems. From what I have read my present Black Gold BGT3540 is said to be a better tuner????

Do you think reception will improve after the full digital changeover?

Reception should improve after switchover, as they are saying that transmission power can then be increased without interfering with analogue channels.
Whether it will actually be increased though - we'll have to wait and see, though as they are currently doing upgrade work on the transmitter network in preparation for switchover, it seems that power increases are likely!

According to Digital UK - Live update , the Sutton Coldfield transmitter is having upgrade work done during Jan-Apr09, and will be having periods of reduced power transmission - your issues could be related!