LinuxMCE Forums

General => Users => Topic started by: joshpond on May 18, 2011, 10:36:20 pm

Title: MythTV trouble shooting.
Post by: joshpond on May 18, 2011, 10:36:20 pm
Hi all,

Onto the next issue:

MythTV playback through a HDHomerun DVB-T

Both live TV playback and recording on the core ends up with a lot of digital artifacts/breakup, similar to poor signal.

I've had the signal strength tested and it is fine.
I've used the hdhomerun's tv software on a windows 7 laptop and the picture is perfect.

It's only and issue through the core and the MD's as well.

Core is
AsRock N68-S3-UCC DDR3 All-In-One DDR3 with
   Integrated NVIDIA GeForce 7025 graphics Max. shared memory 256MB
2GB kingston ram
AMD Sempron 140 2.7GHz
320GB Seagate AV drive

MD  is
Zotac IONITX-A-C

MythTV Version:
Please attach all output as a file in bug reports.
MythTV Version   : 23843M
MythTV Branch    : tags/release-0-23
Network Protocol : 56
Library API      : 0.23.20100429-1
QT Version       : 4.4.3
Options compiled in:
 linux release using_oss using_alsa using_pulse using_jack using_pulseoutput using_backend using_directfb using_dvb using_firewire using_frontend using_glx_proc_addr_arb using_hdhomerun using_hdpvr using_iptv using_ivtv using_joystick_menu using_libfftw3 using_lirc using_mheg using_opengl_video using_opengl_vsync using_qtdbus using_qtwebkit using_v4l using_x11 using_xrandr using_xv using_xvmc using_xvmc_vld using_xvmcw using_bindings_perl using_bindings_python using_opengl using_vdpau using_ffmpeg_threads using_libavc_5_3 using_live using_mheg

I'm not sure what the next step trouble shooting is?
Is it hardware or software?
I think my hardware is up to scratch, The hdd is an AV drive so should cope well.

I'm open to suggestions.

Thanks Josh
Title: Re: MythTV trouble shooting.
Post by: purps on May 19, 2011, 12:09:42 am
It's a dual tuner right? So are you splitting the signal? Or does the homerun just have one input to serve the two tuners?

Your signal strength may be fine, but the signal quality might be poor (there is a difference).

Cheers,
Matt.
Title: Re: MythTV trouble shooting.
Post by: joshpond on May 19, 2011, 03:12:02 am
Yes it is a dual tuner. There is one input so I believe it splits internaly to serve both tuners.

The thing that confuses me is that I don't have problems watching tv using the hdhomerun quickview software on a windows 7 machine.

I read somewhere that with mythtv when It scans it can show signal quality but I've been unable to find that.

Thanks Josh
Title: Re: MythTV trouble shooting.
Post by: purps on May 19, 2011, 12:24:32 pm
The thing that confuses me is that I don't have problems watching tv using the hdhomerun quickview software on a windows 7 machine.

Could it be that the quickview software is only utilising one tuner? Can you use the software to simultaneously record and watch two different channels, just to make sure both tuners are being used?

Either way, I would suggest trying a signal booster. Get one with variable gain. Turn the gain right down, see how it looks, and then gradually increase it until you get the best picture.

Cheers,
Matt.
Title: Re: MythTV trouble shooting.
Post by: totallymaxed on May 19, 2011, 12:32:25 pm
Hi all,

Onto the next issue:

MythTV playback through a HDHomerun DVB-T

Both live TV playback and recording on the core ends up with a lot of digital artifacts/breakup, similar to poor signal.

I've had the signal strength tested and it is fine.
I've used the hdhomerun's tv software on a windows 7 laptop and the picture is perfect.

It's only and issue through the core and the MD's as well.

Core is
AsRock N68-S3-UCC DDR3 All-In-One DDR3 with
   Integrated NVIDIA GeForce 7025 graphics Max. shared memory 256MB
2GB kingston ram
AMD Sempron 140 2.7GHz
320GB Seagate AV drive

MD  is
Zotac IONITX-A-C

MythTV Version:
Please attach all output as a file in bug reports.
MythTV Version   : 23843M
MythTV Branch    : tags/release-0-23
Network Protocol : 56
Library API      : 0.23.20100429-1
QT Version       : 4.4.3
Options compiled in:
 linux release using_oss using_alsa using_pulse using_jack using_pulseoutput using_backend using_directfb using_dvb using_firewire using_frontend using_glx_proc_addr_arb using_hdhomerun using_hdpvr using_iptv using_ivtv using_joystick_menu using_libfftw3 using_lirc using_mheg using_opengl_video using_opengl_vsync using_qtdbus using_qtwebkit using_v4l using_x11 using_xrandr using_xv using_xvmc using_xvmc_vld using_xvmcw using_bindings_perl using_bindings_python using_opengl using_vdpau using_ffmpeg_threads using_libavc_5_3 using_live using_mheg

I'm not sure what the next step trouble shooting is?
Is it hardware or software?
I think my hardware is up to scratch, The hdd is an AV drive so should cope well.

I'm open to suggestions.

Thanks Josh


When we shipped with MythTV 0.23 we had a load of tuning related problems when using HDHomeRun's (a Myth bug and not a problem with the HDHomeRun)... it seems likely you may be suffering that problem too. MythTV 0.24-fixes corrects this problem and many others too by the way.

All the best


Andrew
Title: Re: MythTV trouble shooting.
Post by: brake16 on May 19, 2011, 02:34:11 pm
Quote
MythTV 0.24-fixes corrects this problem and many others too by the way.

Has 0.24 been rolled out yet?
Title: Re: MythTV trouble shooting.
Post by: joshpond on May 19, 2011, 10:38:51 pm
Quote
Either way, I would suggest trying a signal booster. Get one with variable gain. Turn the gain right down, see how it looks, and then gradually increase it until you get the best picture.

Thanks Matt, I've tried an old signal booster that I had and it didn't work but I'm not confident the signal booster is doing it's job.

Quote
Could it be that the quickview software is only utilising one tuner?

Unfortunately I can only view and not record with the software and it only allows one window. I did find the config GUI wich is showing 100% for all signal strength, quality and symbol quality for both tuners when on different channels and they stream around 4 to 8 Mbps So I think the network can cope.

Quote
When we shipped with MythTV 0.23 we had a load of tuning related problems when using HDHomeRun's (a Myth bug and not a problem with the HDHomeRun)... it seems likely you may be suffering that problem too. MythTV 0.24-fixes corrects this problem and many others too by the way.

What is the best way to go to 0.24-fixes. Can 810 be upgraded and how?
Or
Is it best to go to 1004?

Thanks Josh
Title: Re: MythTV trouble shooting.
Post by: theteju on May 22, 2011, 06:01:26 am
I have no problem what so ever with my hdhomerun on myth as of now. I am running 8.10.

Title: Re: MythTV trouble shooting.
Post by: joshpond on May 22, 2011, 08:42:20 am
Is it the DVB-T version or the ATSC. I'm using ATSC,

Just tried mythbuntu 0.24 and it runs fine so like Andrew said it leaves me trying to upgrade the linuxMCE to 0.24 or just moving back to mythbuntu.

Josh
Title: Re: MythTV trouble shooting.
Post by: theteju on May 22, 2011, 08:17:36 pm
i live in FL, so i m sure i am ATSC.
Title: Re: MythTV trouble shooting.
Post by: joshpond on May 22, 2011, 10:13:31 pm
Sorry I meant I'm using the DVB-T version.

Mythbuntu works fine for me.

Josh