[mythtv-users] Suddenly only recording in SD, not HD

[Stephen Worthington]

rOn Fri, 28 Apr 2023 17:27:37 +0100, you wrote:

>Hi,
>
>I have a MythTV setup that has been working very well for a few years.
>Highlights:
>- Proxmox, container with Ubuntu 20.04.
>- Hauppauge dualHD USB stick (passed through), DVB/DVB-T2
>
>Suddenly in the last few days it has stopped being able to tune into
>HD channels, but it can still tune to SD. When trying to tune to any
>HD channel, I get a timeout error:
>TuningSignalCheck: taking more than 5000 ms to get a lock. marking
>this recording as 'Failing'.
>
>The timeout was 3000ms, and I tried increasing it to 5000 but it has not helped.
>
>When tuning in MythTV Frontend, it shows:
>Signal 73%
>S/N 4.7dB
>(TLMs) Partial Lock
>
>Clearly, my hardware is still working. I appear to have decent signal
>quality. I have completely restarted all hardware to eliminate any odd
>issues there.
>
>I am not sure on where my line of enquiry should be to investigate
>further? Does anyone have any suggestions?
>
>Thanks!
>
>Karl

Here in New Zealand we have one channel ("Three") where the channel
timeout has to be at least 7000 ms for it to tune.  I have all my
capturecard.channel_timeout values set to 10000.  Originally,
mythbackend used to do multiple attempts at channel tuning, and with
this channel the first attempt would fail and then a later attempt
would succeed.  When the tuning code was fixed to just do one tuning
attempt and obey the channel_timeout properly, Three stopped tuning
and I had to increase the channel_timeout values.  With 10,000 ms, it
always tunes.  I think that if you create a new database these days,
the default channel_timeout will be 10,000 ms, but if your capturecard
table was created earlier and continuously upgraded, it will have the
older default channel_timeout (3000 ms ???).

Three was not originally different from the other channels, but at
some point in its history some setting was changed in its transmitter
setup that has caused this problem.  So it may be that the transmitter
setup for your HD channels has been changed similarly recently.  It is
certainly worth trying very large channel_timeout values to see if it
helps.