[mythtv-users] Mythtv refuses to set channel on second input

[DG Mailing List]

I've been fighting with a problem for some weeks now and I'm really  
hoping someone can help.

When I upgraded my MythTV box from 0.24 to 0.25 (and even after I  
attempted to upgrade to 0.26 and then did a clean reinstall of 0.25) I  
am unable to successfully change input source on my quad input  
(TBS6984) card.   I doubt the card is faulty as I can use mplayer and  
szap-s2 to watch a channel.

The problem is almost certainly a backend problem as it occurs  
regardless of whether I use a local or remote frontend.  Debugging on  
the backend produces the following when I try to change to input 2   
(when logged with /usr/bin/mythbackend --syslog local7 --user mythtv  
--verbose channel,chanscan)


2012-08-05 07:49:10.984104 I  ChannelBase(27): Looking for  
startchannel '301' on input 'DVBInput'
2012-08-05 07:49:10.986499 I  ChannelBase(27): Found startchannel  
'301' on input 'DVBInput'
2012-08-05 07:49:10.986516 I  TVRec(27): HW Tuner: 27->27
2012-08-05 07:49:10.998797 I  DVBChan(27:/dev/dvb/adapter2/frontend0):  
Opening DVB channel
2012-08-05 07:49:10.998810 I  DTVChan(/dev/dvb/adapter2/frontend0):  
SetChannelByString(301):
2012-08-05 07:49:11.001345 I  DTVChan(/dev/dvb/adapter2/frontend0):  
SetChannelByString(301): failure
2012-08-05 07:49:11.001359 E  TVRec(27): Failed to set channel to 301.  
Reverting to kState_None
2012-08-05 07:49:11.001385 I  TVRec(27): Changing from WatchingLiveTV to None

Similarly I noticed on startup with the following   
/usr/bin/mythbackend --syslog local7 --user mythtv --verbose  
channel,database,decode,dsmcc,dvbcam,general

2012-08-05 08:07:45.783777 I  TVRec(27): Start channel: 301.
2012-08-05 08:07:45.970814 I  DVBChan(27:/dev/dvb/adapter2/frontend0):  
Opening DVB channel
2012-08-05 08:07:45.972537 I  DiSEqCDevTree: Changing LNB voltage to 18V
2012-08-05 08:07:46.972814 I  DiSEqCDevTree: Resetting DiSEqC Bus
2012-08-05 08:07:46.972836 I  DiSEqCDevTree: Sending DiSEqC Command: e0  0  0
2012-08-05 08:07:47.319990 I  ChannelBase(27): Input #20: 'DVBInput'  
schan(301) sourceid(4) ccid(27)
2012-08-05 08:07:47.320006 I  ChannelBase(27): Current Input #20: 'DVBInput'
2012-08-05 08:07:47.320388 I  DTVChan(/dev/dvb/adapter2/frontend0):  
SetChannelByString(301):
2012-08-05 08:07:47.321572 I  DTVChan(/dev/dvb/adapter2/frontend0):  
SetChannelByString(301): failure
2012-08-05 08:07:47.321587 I  ChannelBase(27): Looking for  
startchannel '301' on input 'DVBInput'
2012-08-05 08:07:47.322633 I  ChannelBase(27): Found startchannel  
'301' on input 'DVBInput'
2012-08-05 08:07:47.322869 I  Database connection created: DBManager4
2012-08-05 08:07:47.322887 I  New DB connection, total: 4
2012-08-05 08:07:47.323350 I  Connected to database 'mythconverg' at  
host: 10.0.3.251
2012-08-05 08:07:47.325124 I  TVRec(28): Start channel: 301.
2012-08-05 08:07:47.325186 I  DVBChan(28:/dev/dvb/adapter2/frontend0):  
Opening DVB channel
2012-08-05 08:07:47.325196 I  DVBChan(27:/dev/dvb/adapter2/frontend0):  
Opening DVB channel
2012-08-05 08:07:47.326206 I  ChannelBase(28): Input #21: 'DVBInput'  
schan(301) sourceid(4) ccid(28)
2012-08-05 08:07:47.326217 I  ChannelBase(28): Current Input #21: 'DVBInput'
2012-08-05 08:07:47.326438 I  DTVChan(/dev/dvb/adapter2/frontend0):  
SetChannelByString(301):
2012-08-05 08:07:47.327344 I  DTVChan(/dev/dvb/adapter2/frontend0):  
SetChannelByString(301): failure
2012-08-05 08:07:47.327357 I  ChannelBase(28): Looking for  
startchannel '301' on input 'DVBInput'
2012-08-05 08:07:47.328323 I  ChannelBase(28): Found startchannel  
'301' on input 'DVBInput'



When I debug with --verbose all, I get a screed of information which  
is difficult to parse, but it seems to show the following when I  
change the input:

Aug  5 08:02:21 mythbox mythbackend[3568]: I ProcessRequest  
mythsocket.cpp:671 (readStringList) MythSocket(d2b3a0:60): read  <- 60  
34      QUERY_RECORDER 27[]:[]IS_RECORDING
Aug  5 08:02:21 mythbox mythbackend[3568]: I ProcessRequest  
mythsocket.cpp:345 (writeStringList) MythSocket(d2b3a0:60): write ->  
60 1       0
Aug  5 08:02:21 mythbox mythbackend[3568]: I ProcessRequest  
mythsocket.cpp:671 (readStringList) MythSocket(d2b3a0:60): read  <- 60  
34      QUERY_RECORDER 27[]:[]IS_RECORDING

I am certain that MythTV is not recording anything.

Any help would be very much appreciated.

Thanks,
Ben