Jerky playback from capture device (DVB-T)

[martinu]

(Apologies if this turns out to be a generic problem that's not confined to Windows, but I cannot test it on anything other than Windows so I've no idea whether other operating systems are affected)

I've noticed that if I capture from a DVB-T decoder, using VLC 2.1.4 64 bit either to play live TV (as if it were a television) or to record live TV, I get jerky playback. As far as I can see, the PC isn't struggling (there isn't excessive CPU or memory usage).

Am I doing it the correct way? This is what I do:

- Media | Open Capture Device
- Capture Mode = TV - digital
- Tuner card = 0
- Delivery system = DVB-T
- Transponder frequency = 514000 kHz (one of my DVB-T multiplexes is on UHF 26, centre frequency 514 MHz)
- bandwidth = 8 MHz
- Advanced options = all defaults

- Playback | Program = (select a channel from the displayed list)

This plays in jerks: there's about 1 second of smooth video and sound, then a pause of about 1/2 second and then another burst of smooth video. As far as I can tell, no video/audio is lost: everything picks up exactly where it left off before the pause.

If I press the record button, the whole multiplex is recorded without (as I can tell) and dropped data. But what is recorded is only what is displayed: if I record for 5 minutes, I will only see maybe 30 seconds of video (because the video keeps freezing for 1/2 second every second) and this is all that is recorded.

The PC spec is Windows 7 Home Premium, Athlon II X4 630 2.8 GHz, 6 GB RAM, SATA II hard disk with about 80 GB free space. While V:C is capturing and playing its jerky video, Task Manager | Performance shows about 5-10% CPU usage, spread equally among the 4 CPU cores, with physical memory usage about 50-60%. So it's not hammering the PC so hard that it can't keep up. The DVB-T adaptor is a Hauppauge Win-TV Nova-T DVB-T.

Normal TV playback and recording (eg in Windows Media Centre or Next PVR) records and plays back fine - it's only in VLC that things get jerky.

[Ludrax]

DVB-T regression