Strange 'no signal' issue (1 Viewer)

[mm1352000]

TV Server remembers the previous channel that you viewed on each tuner. That is important when you change channels for two main reasons:

1. If the channel that you try to change to is on the same transponder as the previous channel then TV Server won't try to retune the tuner.

2. For "ProfRed" tuners like yours, even when the tuner gets retuned we try to save the 100ms that it takes to send the DiSEqC command. If the previous channel has the same frequency, port (DiSEqC), polarity (horizontal/vertical/left/right), pilot, roll-off and FEC rate then TV Server won't resend the DiSEqC command.

You were testing Kika -> Kika.

For point 1: TV Server should have known that it didn't need to retune the tuner since it was already tuned to the correct transponder (even the same channel in this case), however there is actually a small bug in MP 1.1.x which means that your TBS tuners (and some others) will always retune. That is not a big problem - it might just take a little longer to switch between channels.
For point 2: TV Server realised it didn't need to resend the DiSEqC command, so it didn't send it.

2011-02-19 10:56:46.946089 [(10)]: ProfRed: already tuned to diseqc:Level1AA, frequency:11954000, polarisation:LinearH

I thought that might be the problem. In other words, I thought that maybe your tuner needs to resend the DiSEqC command even if it was already switched to the correct port on the switch...

I can't explain why the issue has suddenly disappeared after a reinstall; a reinstall should have made no difference. Perhaps the EPG grabber is sometimes using the tuner between your attempts to change channel. If the EPG grabber tuned to a different transponder then it would mean TV Server would have to retune and resend the DiSEqC command when you next wanted to use the the tuner. That is just a guess though. If this problem happens again, try tuning to a channel on a different transponder. That will force TV Server to retune and/or resend the DiSEqC command, and that should make the tuner start working again.

I hope that makes sense.

 

[dkoscak]

Just as I thought, after one day working perfectly, it happens again - no switching from DVB-T to DVB-S allowed!

It doesn't matter which transponder is used, moreover I analized sending of DiSEqC commands and everything seems ok... Also the problem is not anyhow related to EPG grabbing because it's turned off temporarily until I solve this problem. It's quite possible that there's no problem in Mediaportal itself ...

If I fail to conclude anything else, I'll try to implement some kind of 'light/fast graph rebuild' without releasing all the plugins (if that is possible at all) ONLY when this no signal issue happens... Don't know if this could generally be helpful for others...

 

[mm1352000]

Hi again

You can test whether rebuilding the graph will help using a debug option. Try this:

1. Open a command line (nasty I know, but bear with me!).
2. Change directory to your TV Server install directory (example: cd "C:\Program Files\MediaPortal 1.1.2\TV Server").
3. Type SetupTv.exe --DebugOptions.
4. TV Server configuration should start with a new section in the left hand side called "Debug Options".
5. Try turning on "always reset graph after stop".

Warning: debug options are not for playing with unless you know what you're doing.

That option will reset the graph for a tuner each time TV is stopped.

 

[dkoscak]

Yes, everything is working OK when I use 'rebuild graph' option, as I described in post #5 ... But rebuilding happens too often, reduces zapping time and sometimes crashes TV server when releasing plugins ... I'd like to rebuiled only when I have to - that is, when I get 'no signal' error and even would like to do only partial Dispose() ... Maybe this I way I could figure out which part of all this is causing problems I'll see what can be done in next few days.

 

[mm1352000]

Hi again dkoscak

I'm interested to know if you managed to resolve this issue. Some one else has raised a similar issue over here and they say that preloading the DVB-T card may resolve the problem...

 

[dkoscak]

Hi mm1352000!

Unfortunately I didn't resolve this issue I haven't been playing with it since I had only a little bit of free time and I'm not using dvb-t that much, but I would like to know what is happening. I'm not able to activate preloading of dvb-t card - this option is disabled (grayed). Only can set preloading of dvb-s card, tried this, doesn't make any difference. What affects on the posibility to preload card - maybe I can't do it because it's the hybrid card - I have 2 dvb-t and 2 analog entries and neither one gives the posibility of preloading.

But it's relieving to hear that somebody else is having the same problem - it means I'm not crazy And maybe we'll come up to some solution easier ... Tnx!!

And btw, I posted similar issue on TBS forum, but they have no idea what could be the problem ...

 

[mm1352000]

Unfortunately I didn't resolve this issue

I'm not able to activate preloading of dvb-t card - this option is disabled (grayed).

As you've guessed, this is because the tuner is hybrid.

But it's relieving to hear that somebody else is having the same problem - it means I'm not crazy And maybe we'll come up to some solution easier ... Tnx!!

And btw, I posted similar issue on TBS forum, but they have no idea what could be the problem ...

It is like there is some kind of hardware incompatibility or conflict, but it is not clear exactly where the problem is yet. What brand of motherboard do you have?

 

[dkoscak]

I have Gigabyte 880GM-UD2H motherboard. There are no 'official' conflicts in Windows, everything is reported to be functioning without problems in Windows Device Manager. Also, latest motherboard drivers are applied in the system.

It would be interesting to know how dvbviewer handles graph (re)creation when switching between different cards...