I just started having a problem with one of my local channels the last 4 weeks... I change to the channel, there's a second of sound and then the sound stops and the video starts playing about half speed. I'm getting a 90% signal and a lock but I'm still having this issue.

I'm running Mythtv .20 on Ubuntu 6.10 AMD 64 with 2 pchdtv 5500 cards and other than this issue its been running pretty good.

Any ideas?

Does it happen on both tuners (press Y in live TV to switch)? Does it only happen in live or also on all recordings? How does the channel look on your TV with a direct cable connection?

Yep, it happens on both tuners and both in live and in recordings. I haven't been able to watch this HD channel directly, its OTA and my current tv does not have an HD tuner.

I have one other channel that's been like this since I first setup myth, but it wasn't a real issue because its a duplicate ABC channel.

I tried typing some numbers into mythweb into the finetune column on the channel page with no difference.

Is it possible that the broadcast format is behind this?

What I mean is that some stations broadcast as 720p, and some as 1080i. My info says that ABC and FOX are 720p, all other OTA networks are 1080i.

The current channel thats screwed up is Fox.... and the strange thing is that it used to be the best looking channel. It started doing the slow-motion thing just after the prime time shows ended in May. With CBS I have some weird scan-line issue when quick movement happens in the programming, but its watchable... NBC, my other ABC channel and PBS work fine.

My tv isn't really HD, its Enhanced definition... its a RCA MM36100. I have it running at 800x600.... the tv is supposedly capable of doing 950/700 but I couldn't get that resolution to stick.

Interesting.... I fired up Mythtv Player from a laptop I had at home and tried playing something I just recorded from Fox and it seems ok. So it looks like its actually recording/saving the video and audio ok, just for some reason mythtv isn't playing it back correctly on Live Tv and from the recording itself.

In the MythTV setup in the main program (not the mythtv-setup program), what are you using for deinterlace? I have always had good luck with BOB.

I think I'm using one of the first 2 options, either the Linear blend or the Kernel one.

The video card I'm using is the onboard Geforce 6150 (M2NPV-VM motherboard)

Other specs:

AMD Athlon 64 X2 3800+(65W)
Ubuntu 6.10 AMD64 version
1GB Dual Channel SDRAM DDR2 800 (PC2 6400)

I would try changing the deinterlace method, to see what effect it has. You may also want to try a different mpeg2 decoder. I was using Standard XvMC because I use the nVidia driver. I found that it wasn't working properly, and switched to Standard (ffmpeg).

The way that I found that I had a problem, was to run the frontend in verbose mode. Use the -v option, type in mythfrontend --help for more options.

I was using the Kernel one... tried switching to Bob, with no change. I also was using the Standard decoder and tried the Standard XvMC one, also with no change. Its strange why this is only affecting certain channels and all the other channels playback fine.

I just realized that you are using on-board video (Doh!). That seems to rarely work for HDTV. You may need to use a video card for better playback.

I tried running mythfrontend in -v all,nodatabase and saw these results

2007-07-27 19:33:33.354 NVP: Video is 11.5827 frames ahead of audio,
doubling video frame interval to slow down.
2007-07-27 19:33:33.354 NVP: A/V Divergence: 11.9388, Rate: 0.356111, Warpfactor: 1.0938, warpfactor_avg: 1.00105
2007-07-27 19:33:33.359 AO: audio waiting for buffer to fill: have 2048 want 4096
2007-07-27 19:33:33.359 AO: Broadcasting free space avail
2007-07-27 19:33:33.361 AFD: video timecode 815104824 815104824 9056720 9056049
2007-07-27 19:33:33.363 AO: audio waiting for buffer to fill: have 2048 want 4096


Does that mean the audio can't keep up? I'm also using the onboard audio as well.

I tried enabling the extra audio buffering even though it said:

Enable this setting if MythTV is playing "crackly" audio and you are using hardware encoding.

The audio wasn't crackly and I'm not using hardware encoding.... but after I enabled it, watching Live Tv and playing back a recording worked great. Not sure what caused the audio and video to get out of sync like that, maybe its the quality of the signal or something? .... but its back to working normally.

Thanks for the help.

Cool!

So running in verbose did help, it's great that you got it to work the first time.