[mythtv-users] BBC Radio 7 stuttering

[Rob Willett]

Hi,

Well the saga continues...

90% of the reason to get a Myth installation was to record old BBC comedy radio
shows being transmitted on BBC Radio 7 on DVB.

The problem now is that the audio is stuttering on BBC Radio 7. BBC Radio 1 - 4
all work fine. They have the correct audio pid and another video pid from
channel 5 if my recollection is correct. No problem's on audio at all.

I've done the same with Radio 7 and the sound just stutters and hangs, free's up
and then hangs again every second or so. All the other radio stations sound OK.

Odd!

The scan for BBC Radio 7 on the Crystal Palace transmitter is here, I've put my
own line endings in to make it easier to read.

BBC 7:529833330:INVERSION_AUTO:BANDWIDTH_8_MHZ:\
FEC_3_4:FEC_3_4:QAM_16:TRANSMISSION_MODE_2K:\
GUARD_INTERVAL_1_32:HIERARCHY_NONE:0:433:18112
BBC FOUR:529833330:INVERSION_AUTO:BANDWIDTH_8_MHZ:\
FEC_3_4:FEC_3_4:QAM_16:TRANSMISSION_MODE_2K:\
GUARD_INTERVAL_1_32:HIERARCHY_NONE:201:401:16832
BBC Radio 4:561833330:INVERSION_AUTO:BANDWIDTH_8_MHZ:\
FEC_2_3:FEC_1_2:QAM_64:TRANSMISSION_MODE_2K:\
GUARD_INTERVAL_1_32:HIERARCHY_NONE:0:6258:14528

I noticed that the FEC for BBC 7 is normally FEC_2_3 rather than the Radio 4
version of FEC_2_3 but most of the setting (all the settings!) apart from the
video PID are the same as BBC Four which works very well. 

I've edited the MySQL tables by hand to add every channel I have in as that
seems easier and quicker. Every channel works well apart from BBC Radio 7. 

I get the following errors on the mythfrontend terminal screen when tuned to BBC
Radio 7.

Audio Buffer overflow, audio data lost
Audio Buffer overflow, audio data lost
Audio Buffer overflow, audio data lost
Audio Buffer overflow, audio data lost
Audio Buffer overflow, audio data lost

repeated ad infinitum.

I have exactly the same problem on recordings made from Radio 7 as well, which
would indicate that the problem is at the front end of the system rather than
the back end of the system.

I've looked through google and as many of the archives as I can and have seen
some references to this problem but no obvious solution. 

The hardware spec of the machine is an Athlon 2800/512MB RAM/2x160GB Seagate
disks which should be enough to handle an audio stream <grin>.

I have the latest version of the Alsa drivers 
alsa-driver-1.0.4
alsa-lib-1.0.4
alsa-utils-1.0.4

Very perplexing. Solutions or suggestions welcomed.

Rob.


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