[mythtv-users] Video card update fail

[Stephen Worthington]

On Thu, 11 Oct 2018 16:57:43 -0700, you wrote:

>The list god said that my response was too large so I cut off everything
>but my response.
>-----------------------------------------
>Thanks so much for all your help.  Hopefully I can get my system working
>satisfactorily again.
>
>There is a lot of territory covered here.
>
>The settings of Alsamixer with "line" muted are the same as what worked
>with the 6200 card and unmuting "line" does not help and in fact
>Alsa:default doesn't play anything. I just tried it to make sure. Not sure
>if you picked up on the fact that I only get analog when the Nvidia sound
>card is selected in Myth.  As the Nvidia sound card does not have an analog
>output I find that strange.  Most of the settings that work on ALSA are
>digital outputs.
>
>A bit of history.  With Mythbuntu8 I had a lot of trouble getting SPDIF to
>work and when I did I wrote the Digital Audio HowTo which still exists
>largely as I wrote it.  But at that time I was not able to get analog and
>digital to work at the same time. I had a Surround decoder that I used from
>the second SPDIF output on the motherboard.  It is a connector on the MB
>and not on the back panel.  But in troubleshooting things I power cycled
>the decoder and it never worked again. When I installed Muthbunty 16 I was
>able to get SPDIF and Analog at the same time with the 6200 card. That
>stopped when the 750 card was installed.  My thought is that I should
>remove Pulse Audio but I was able to get analog and SPDIF with Pulse
>installed so I have not done it.

Yes, that is very strange.  Where is your analogue output plugged
into?  As you say, the Nvidia card does not have an analogue output,
and I have never heard of ALSA being able to send output to two
different cards without a special /etc/asound configuration.  Pulse
can, so that is a candidate for causing this problem.  So removing it
is probably the next thing to do.  If you have any worries about
removing Pulse, you can download a copy of Clonezilla and use it to
make an image backup of your system partition before trying, so that
you can then restore from that image if something goes wrong.

>The system has one hard disk where the Mythbunty8 initially had one but at
>some point I added a second.  It worked fine with one disk.  On the
>Mythbuntu8 system we would sometimes record 3 or 4 shows without issue.  On
>these latest tests, there was only a single channel being recorded.

Three recordings at once usually works, but occasionally may cause
problems.  Depending on the hard drive, four at once may be fine, or
may cause problems, especially if it is also the system disk.  It also
depends on how full the disk is, as the heads have to move more often
and further when the disk is full.  I do not recommend recording more
than three programmes at once to a hard drive.  SSDs are likely much
more capable, due to not have any heads to move, but they have other
problems when used for recording.

>Virtually all the source material we watch is 720p.  It is OTA HD @720p
>some stations here are 1080i but we tend not to watch them. Therefore, 720p
>seemed like the choice that would involve the least conversions.

If absolutely all your files were 720p, it would be OK to run the TV
at 720p, but it is better to get things to match properly so you can
play other sizes and frequencies without problems.  Most people also
use the MythTV box for playing downloaded files and DVDs and BluRay
disks, and a lot of that is 1080p, or even 4K these days.  The best
setup has the GUI running at the best the display can do, and
switching the display mode to match the video source wherever
possible.  When an exact match is not possible, then there are two
ways that work well.  One is to have the display running in as
compatible a mode as possible, and the output from the Nvidia card
should be matching that mode.  The other way is to have the Nvidia
card output matching the video source mode, and the TV able to take
that mode and convert it for display.  But since TVs and monitors
often lie about their capabilities in their EDID data, this second
setup can be very difficult to do, so the first is recommended, and it
normally works out that the display is run in 1080p mode and the
Nvidia card is converting from whatever the video mode is to 1080p.

The key thing in the setup is to have only one conversion of the video
data - having two conversions almost always causes troubles.

>I found the input name on Mythweb.  It is in the details for the program
>for example  "Input Name: 1: MPEG2TS". This would indicate that the tuner
>that recorded the shows with problems is turner 1 and it has 100% signal
>strength.  Not likely a signal issue although it could be a power supply
>issue with the HDHomerun as I have seen that before. I will check that.  I
>will also have to look into logging the recordings as suggested.  Seems
>like the only way to get an idea of what is going on.
>
>Allen

That is a useful discovery - I did not know MythWeb showed that data.
But if it is there in the database and MythWeb shows it, the I-I
display should also show it.  Since you are running your screen in
1280x720 mode, it is more than likely that you would need to scroll
that screen down to see the "Recording Input" line.