[Solved] No lock when changing channels

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dschey758
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Joined: Mon Nov 03, 2014 8:11 pm
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[Solved] No lock when changing channels

Post by dschey758 » Thu Jan 03, 2019 1:30 pm

Hi,

summary of the problem: i can watch LiveTV, but when changing to some other channels, i get no lock. When i change source to the other input, the channgel works!

My setup: mythtv 0.29.1 fixes 20181228 on mythbuntu 16.04, Dual tuner DVB-S2 card (TBS 6980).

For some years i was running mythbuntu 14.04 and now wanted to upgrade to have new software and because some programs always produced empty files when recorded.
So i upgraded to 16.04, did a new channel scan. I can watch e.g. (ASTRA, europe) "Das Erste HD", but when switching to "3sat" (probably on another transponder) it gets no lock. When i change source, then it works.
Whatever i do, the problem described above doesn't go away.
I configured the 2 tuners, one video source and 2 input connections of the tuners to the video source.

I even tried dropping the database and setting up everything from scratch, but still the same.

The card is a TBS-6980. I think i'm using the drivers included in the kernel..... may this be the problem? Or did i do something wrong with the channel scan?

jksj
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Posts: 64
Joined: Thu Feb 13, 2014 7:53 pm
Great Britain

Re: No lock when changing channels

Post by jksj » Sun Jan 06, 2019 1:12 pm

The driver for the TBS DVB cards is not included in the kernel. I don't understand how you get any signal.
See https://linuxtv.org/wiki/index.php/TBS6980 for the link to the open source driver

dschey758
Newcomer
Posts: 7
Joined: Mon Nov 03, 2014 8:11 pm
Germany

Re: No lock when changing channels

Post by dschey758 » Tue Jan 08, 2019 2:21 pm

Ok, maybe i mixed this up. When i have read open source driver, i thought it was included in the kernel already.

I at least tried to install the TBS driver from their download page and remember that i had problems, but don't remember if i finally succeeded or just tried to run mythtv and it worked out of the box (so i was assuming there are built in drivers).

I'll check and post an update here.

dschey758
Newcomer
Posts: 7
Joined: Mon Nov 03, 2014 8:11 pm
Germany

Re: No lock when changing channels

Post by dschey758 » Tue Jan 08, 2019 10:21 pm

I guess i had the TBS drivers installed, but now i have successfully reinstalled the latest drivers from TBS (v170330). Problem is the same.

Here is the mythbackend.log

Code: Select all

Jan  8 23:12:58 jay-mythbox mythbackend: mythbackend[1137]: I TVRecEvent tv_rec.cpp:3665 (TuningFrequency) TVRec[11]: TuningFrequency
Jan  8 23:12:58 jay-mythbox mythbackend: mythbackend[1137]: N CoreContext autoexpire.cpp:251 (CalcParams) AutoExpire: CalcParams(): Max required Free Space: 6.0 GB w/freq: 14 min
Jan  8 23:12:58 jay-mythbox mythbackend: mythbackend[1137]: W TVRecEvent programinfo.cpp:5614 (LoadFromProgram) LoadFromProgram(): SQL contains LIMIT clause, caller should be updated to use limit parameter instead
Jan  8 23:12:58 jay-mythbox mythbackend: mythbackend[1137]: N TVRecEvent recordinginfo.cpp:695 (ApplyRecordRecGroupChange) ApplyRecordRecGroupChange: LiveTV to LiveTV (2)
Jan  8 23:13:05 jay-mythbox mythbackend: mythbackend[1137]: E TVRecEvent tv_rec.cpp:3962 (TuningSignalCheck) TVRec[11]: TuningSignalCheck: Hit pre-fail timeout
Jan  8 23:13:08 jay-mythbox mythbackend: mythbackend[1137]: W TVRecEvent tv_rec.cpp:3993 (TuningSignalCheck) TVRec[11]: TuningSignalCheck: taking more than 10000 ms to get a lock. marking this recording as 'Failing'.
Jan  8 23:13:08 jay-mythbox mythbackend: mythbackend[1137]: W TVRecEvent tv_rec.cpp:3995 (TuningSignalCheck) TVRec[11]: See 'Tuning timeout' in mythtv-setup for this input

jksj
Junior
Posts: 64
Joined: Thu Feb 13, 2014 7:53 pm
Great Britain

Re: No lock when changing channels

Post by jksj » Wed Jan 09, 2019 9:34 am

Things to try:-
If live TV is more reliable than recording change the quicktune setting in the tuner setup so that it is the same for both.
Check that EIT (if used) is only selected for one tuner.
If you only use one of the tuners ie delete the second one in mythtvsetup is the system completely reliable?
If so double the tuning timeouts.

dschey758
Newcomer
Posts: 7
Joined: Mon Nov 03, 2014 8:11 pm
Germany

Re: No lock when changing channels

Post by dschey758 » Wed Jan 16, 2019 7:14 pm

Thanks for your help and time!

I have now found the cause of the problem: the order for LiveTV of the 2nd tuner (or better: input connection) was set to 0!
This deactivates it for LiveTV. I think i messed this up during setup.

Now LiveTV works again!

BUT: now another (similar) problem is back, which i had already before i upgraded to mythbuntu 16.04. Recordings don't work on all channels. And it looks like its these channels that were not working in LiveTV before... I'll have a look at the logs and open another thread for this problem.

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