[mythtv] DVB lock up - mythtv unusable

[Leandro Dardini]

This is a long standing problem and I hope someone can finally write a good
solution.
With DVB if you tune a channel and for whatever reason (it is encrypted, it
is not broadcasting, signal is weak....)
backend can't read data from the capture card, mythtv frozen and you cannot
change channel.
>From mythtv-backend I get:

2005-03-01 12:31:19.083 DVB#0 Status: LOCK.
2005-03-01 12:31:19.083 DVB#0 Multiplex Locked
2005-03-01 12:31:20.827 DVB#0 Successfully tuned to channel 33.
2005-03-01 12:31:20.857 DVB#0 Data read from DMX - This is for debugging
with transform.c
2005-03-01 12:31:35.851 Couldn't read data from the capture card in 15
seconds. Stopping.

On the mythtv-frontend I get:

2005-03-01 12:31:25.860 taking too long to be allowed to read..
2005-03-01 12:31:30.861 taking too long to be allowed to read..
2005-03-01 12:31:39.853 Waited 4 seconds for data to become available,
waiting again...
2005-03-01 12:31:43.854 Waited 4 seconds for data to become available,
waiting again...
2005-03-01 12:31:47.855 Waited 4 seconds for data to become available,
waiting again...
2005-03-01 12:31:51.857 Waited 4 seconds for data to become available,
waiting again...
2005-03-01 12:31:55.858 Waited 4 seconds for data to become available,
waiting again...
2005-03-01 12:31:59.860 Waited 4 seconds for data to become available,
waiting again...
2005-03-01 12:32:03.861 Waited 4 seconds for data to become available,
waiting again...
2005-03-01 12:32:07.862 Waited 4 seconds for data to become available,
waiting again...
2005-03-01 12:32:07.862 Waited 14 seconds for data to become available,
aborting

DVB card is now tuned on channel 33, but while I cannot read data, I cannot
escape from it. Changing channel is not possible.

What possible solution can be found to what to me seem to limit the use of
DVB on mythtv?

On my DVB set-top-box, if I tune an encrypted channel, a sign appears saying
me "it is an encrypted channel". If the signal is weak, a red dot appears on
the right corner, and so on for every possible malfunction. Can be possible
a similar behaviour also in mythtv? Can the backend outputs a fake stream of
data when it receives no data so the frontend can continue to play and
change channel?

Thank you

Leandro