Unable to start graph / start timeshifting... Timed out waiting for PMT (2 Viewers)

[jonesdb]

Wow! This thread sure got quiet suddenly. Was a solution found for everyone? I have had this problem ever since I installed 1.0.2. on an XP SP3 machine using and AverMedia M780 card on a cable (clear QAM) system. Error appears to be random. Always shows:

WaitForPMT: Timed out waiting for PMT after 10 seconds. Increase the PMT timeout value?

in the log when error occurs. Sometimes restart of TVServer fixes the problem and sometimes requires a re-boot of PC. I use MP mostly for recording and not for live TV. Recently I left the system on for a week while I was gone. Recordings were fine for the first 4 days, then problem started and no recordings after that point on any channel.
Hoping a solution was found.

 

[Imokles]

No solution at least as far as I am concerned. I'm also still hoping for an answer/ fix/ workaround. Attached logs on last page.

 

[thewan]

jonesdb

I had the exact same problem - seemed to manifest itself after an "Upgrade" to 1.0.2 and a fresh channel scan, intermittent unable to start graph erors. I got around it by importing a channle list from an older version then the problem went away but I couldnt scan for new/moved channels However this now seems to be fixed for me and by doing one of the following:

Did a channel scan from a .DVBC file (Not the autotune) <--- I am pretty sure this fixed it for me!
Upgraded drivers for the DVBC card
Removed MP completely and installed MP1.1 aplha from scratch

I am pretty sure that scanning from the file fixed it as just after I scanned from this file several channels that consistently gave me the error didnt so I would try that approach first.

The file is pretty easy to craft, it is just a CSV file of Freq,QAM,SymRate like so:

98750,64QAM,6952000
106750,64QAM,6952000
114750,64QAM,6952000

As long as you have the default freq this file is fairly easy to build with Excel or you ma be able to use one of the existing ones there already - i had to build one for my frequency steps.

HTH

T

 

[morpheus_xx]

just one note to tuning details: https://forum.team-mediaportal.com/...ls-296/new-structure-tuning-parameters-67396/
all newer svn use them.

 

[jonesdb]

Thanks for the feedback.
I don't think the issue is with tuningParameters file though. As I understand the process the tuningParameters file is only used during the scan process. Once stations have been identified and written to the database, only the information in the database is used change the active channel. Thus, every time you select a channel the same data is being read from the database. I have a log file (applicable parts attached) that has recorded two shows one after the other on channel 59 and then tried to record a third show on that same channel after a one hour delay. TVServer was not used during the delay period. I should also let you know that I have disabled EPG gathering for the time being, so that should not interfere with the process. The third show failed to find the PMT and subsequently didn't record anything, even though the client showed a record light and TVServer setup showed a show being recorded. I have compared the log entries for each of the three shows and everything looks identical up to the point of not finding the PMT. I have had another log where three programs were scheduled for recording on the same channel. The first and third recorded fine, but the one in the middle didn't find the PMT and didn't record. Sorry, I didn't keep the log. The 1400 and 1500 logs are for the shows that found the PMT and the 1700 log is the show that failed.
Given the above, I'm actually leaning toward believing it is a problem in the parsing of the transport signal for the PMT information. Any other thoughts?

 

[thewan]

Dont know - all i know is that i had this problem with every version from1.0.0 onwards and to "fix" it i imported an old channel list which always sorted it.

Then i tried 1.1 and still the same problem until iscanned from a dvbc file - now no problems - tunes and records OK.

What you say abopve may well be true - all i can tell you is that the steps abopve fixed the problem for me!

T

 

[nealeb]

I am still finding my way around this forum but today I tripped over the Bugtracker area. I do not see (although I may have missed it) this bug in any of the outstanding/being worked/resolved areas. Has anyone reported it as a "proper" bug? I know that there are some "developer only" areas and I'm not sure if the bug reporting system (although I haven't actually found one yet) is in that category.

It seems that the problem affects at least DVB-C and DVB-T systems and may be associated with things like dynamic changes of PMT in the broadcast signal, leading to MP losing track of where stations are in the multiplex. That certainly seems consistent with what I have seen. However, I still wonder why only a relatively small number of us seem to be affected.

I am regretfully continuing with DVBviewer although I would really have liked ForTheRecord functionality with MP to reliably record for me while I am away for the next few weeks. Ho hum...

 

[Imokles]

I am still finding my way around this forum but today I tripped over the Bugtracker area. I do not see (although I may have missed it) this bug in any of the outstanding/being worked/resolved areas. Has anyone reported it as a "proper" bug? I know that there are some "developer only" areas and I'm not sure if the bug reporting system (although I haven't actually found one yet) is in that category.

I think it should be this one: 0002337: TvServer times out waiting for PMT - MediaPortal Bugtracker
Scheduled for 1.1.0, but severity minor. Let's hope for the best.

 

[jonesdb]

I actually believe that there are at least two problems that show similar symptoms. (At least for me, this seems to be the case)
First, I'm on cable using clear QAM, so the situation maybe somewhat different for satellite.

First Problem.
The cable company does change the PID number associated with a particular PAT program number (ServiceID or cable program channel ...i.e. History channel) at seemingly random points in time, though these don't change often (every few months). When it does occur, MP won't tune that particular ServiceID (program channel) any longer as the PMT PID no longer exists. MP keeps track of the expected PMT PID in the tuning details table along with the ServiceID (PAT program number). The result when such a change takes place is a PMT timeout error and no recording or live TV. If I update the tuning details to reflect the new PMT PID for that particular ServiceID everything is back to normal. (I have a Sony DVR that doesn't have any problem with such changes, as it just looks up the new PID for that PAT program number.) I believe that storing the ServiceID and the associated PMT PID this was done to produce a quick response when changing channels (programs). It would be a great help if MP would update the PMT PID in the tuningDetails table for that particular ServiceID when the PMT PID is not found during the tuning process.

Second problem.
Sometimes the PMT PID search just does a timeout. I have found no reason for this. I have tired extending the search time with no improvement. I have checked for existence of the PMT PID with TSReaderLite right after a PMT PID timeout and the PMT PID exists. I have had MP tune to a PMT PID and record the program, wait an hour and try to retune the same PMT PID and timeout, wait another hour and try to tune the same PMT PID again and be successful.

The second problem is more bothersome to me as the result is that MP seems to randomly not record some of my scheduled programs. I have not been able to identify anything in the logs that is different during these incidents.

 

[DJBlu]

I actually believe that there are at least two problems that show similar symptoms. (At least for me, this seems to be the case)
First, I'm on cable using clear QAM, so the situation maybe somewhat different for satellite.

First Problem.
The cable company does change the PID number associated with a particular PAT program number (ServiceID or cable program channel ...i.e. History channel) at seemingly random points in time, though these don't change often (every few months). When it does occur, MP won't tune that particular ServiceID (program channel) any longer as the PMT PID no longer exists. MP keeps track of the expected PMT PID in the tuning details table along with the ServiceID (PAT program number). The result when such a change takes place is a PMT timeout error and no recording or live TV. If I update the tuning details to reflect the new PMT PID for that particular ServiceID everything is back to normal. (I have a Sony DVR that doesn't have any problem with such changes, as it just looks up the new PID for that PAT program number.) I believe that storing the ServiceID and the associated PMT PID this was done to produce a quick response when changing channels (programs). It would be a great help if MP would update the PMT PID in the tuningDetails table for that particular ServiceID when the PMT PID is not found during the tuning process.

Second problem.
Sometimes the PMT PID search just does a timeout. I have found no reason for this. I have tired extending the search time with no improvement. I have checked for existence of the PMT PID with TSReaderLite right after a PMT PID timeout and the PMT PID exists. I have had MP tune to a PMT PID and record the program, wait an hour and try to retune the same PMT PID and timeout, wait another hour and try to tune the same PMT PID again and be successful.

The second problem is more bothersome to me as the result is that MP seems to randomly not record some of my scheduled programs. I have not been able to identify anything in the logs that is different during these incidents.

Thanks for the information.

I am currently working on a fix for this problem. The PMT Pid change is implemented, just got to set it up to search the PAT when a timeout occurs.