Tvheadend

did you use "Add DVB Network by location... " to add the initial muxes? or did your manually enter the first mux and set tvheadend to "Autodetect muxes "?

which sat is this?

Added DVB network, ASTRA 19.2E, and it added the initial mux. Then autodetect muxes. This creates both the good and bad muxes. I receive 99 muxes that way.

I now removed the initial mux, added the 3 correct muxes manually. All services are detected. Autodetect was switched off.
After switching the autodetect back on, the invalid muxes are added:
Aug 14 13:24:35 dvb: New mux "12,344,000 kHz Horizontal (Default (Port 0, Universal LNB))" created by automatic mux discovery
Aug 14 13:24:35 dvb: New mux "12,515,000 kHz Horizontal (Default (Port 0, Universal LNB))" created by automatic mux discovery
Aug 14 13:24:35 dvb: New mux "12,574,000 kHz Horizontal (Default (Port 0, Universal LNB))" created by automatic mux discovery
Aug 14 13:24:35 dvb: New mux "12,722,000 kHz Horizontal (Default (Port 0, Universal LNB))" created by automatic mux discovery

I have not re-added the initial mux, and therefore I assume it does not detect any further muxes. After the autodetect process above no new service were created, and I deleted the bad muxes again.

In the original scenario full autodetect with initial mux, deleting the bad muxes did not make TVheadend create the services from the good muxes.

if they are added by automatic mux discovery then these muxes are present in the DVB NIT information tables that are transmitted on this network.

It would be good to find out where they are coming from, but this is not something that can be fixed within tvheadend. If these muxes are really incorrect, then the NIT information is incorrect and that is not something tvheadend can correct automagically.

I assume that TVHeadend actively uses the muxid for storing information, and once it has a certain muxid in its database identical muxids will not be scanned anymore on a different transponder. Even though this may be theoretically correct, in practise it seems that Astra (or Canaldigital) does not adhere to the standards.Neither my personal sat receiver nor mythtv seems to mind about the duplicate id's though.
Not being familiar with the standards, I do not know if the muxid should be unique per transponder, per satellite or per satellite constellation. TVHeadend seems to tend to use the first approach.

Workaround: add the correct muxid first, then perform an automatic scan using the initial transponder. Due to the implementation in TVHeadend, the incorrect muxids will not be used.

Johan,

As far as i can tell this problem can only be found if it can be determined which NIT table is adding the incorrect muxes.

The dvb-s astra 19.2 initial tuning file is only adding the 12551.500 frequency. All the other muxes are determined from there on. Because you also see this happening when you manually add only the 3 good transponders, the NIT table that is causing this problem must be transmitted on one of these 3 transponders.

So it would be a matter of taking the NIT table that is transmitted on those frequencies and checking what information is in those tables. Then we can determine if the actual transponders are sending incorrect data, or that tvheadend reads it incorrectly.

You could create a mux dump for these tables and then analyze them using dvbsnoop or an other dvb analysis tool. (have a look at this one: http://www.digitalekabeltelevisie.nl/dvb_inspector/ )

You can create the mux dumps directly from tvheadend by enabling the mux dump option, and then tune to a service on these transponders. This will create a dump of the mux in the recording directly in a separate directory.

Hein

DVBsnoop output:
dvbsnoop 0x10 |grep Frequency
Frequency: 19088384 (= 12.34400 GHz)
Frequency: 19207424 (= 12.51500 GHz)
Frequency: 19231744 (= 12.57400 GHz)
Frequency: 19341824 (= 12.72200 GHz)
Same on two out of the 4 transponders. I can attach a full dvbsnoop 0x10 output if required or run it with different options. Let me know.

Johan