Troubleshooting:Error was encountered while displaying video
The "Error was encountered while displaying video" message is a catch all for a large number of different types of error conditions. The most common is when there is a timeout waiting for video to start for whatever reason. The timeout is not supposed to start counting until we have a good signal. This can fail if the recorder does not have a signal monitor, if the signal is encrypted, or if the signal disappears after the signal monitor reports that it is good. The first two need to be fixed, the last one can't be fixed on all hardware, but we've talked about fixing it with some hardware. This can also happen if you flip channels very quickly. Fixing that problem is a long term project because we don't count frames in the NVP, we count bytes, and this sometimes fails. Counting frames depends on fixing #799, and some display problems I'm working on on the mythtv-vid branch. A quick fix would be to just limit you to one channel change every two minutes, but I think that is not a good solution since 99% of the time for a DVB-T/DVB-C or ATSC/QAM user a channel change completes in 1-3 seconds. There was another problem in 0.19 that made the quick succession of channel changes especially sensitive to frame count estimation errors, which was the problem which the logs in ticket #1153 showed. This problem was worked around by Issac in SVN head, and hence the closing of the ticket. The underlying problem with the estimation throwing off ring buffer switching is still there, but usually only triggered by aggressive channel flipping, and on very rare occasion when we move from one program to the next in LiveTV.
There appears to be a fix for this coming for 0.21, the ticket is here: #2335
Meanwhile some people have found the following to help.
Unchecking the the "Wait for SEQ" for DVB cards in mythtv-setup for each of your cards or you could just use the following mysql command
mysql -e "update capturecard set dvb_wait_for_seqstart = 0 where cardtype = 'DVB'" mythconverg
This also has the side effect of improving channel change speed