[mythtv-users] HD-3000 Partial Channel Locks

[John Welch]

I have an HD-3000 tuner card with a Comcast cable line connected
directly to it.  In the process of identifying the QAM-256 channels
that I could tune using atscscan and mplayer, I found a few channels
where I could get a perfect picture, but no sound.  With a similar
cable line connected directly to a Sony HDTV I get the same behavior
on these channels (picture, no sound).  So I know it's not an issue
with the HD-3000 card or anything like that; just something in the way
Comcast is broadcasting these channels.  Now, the case can be made
that these channels are worthless without audio, but some of them have
sporting events on where I either don't care about the audio, or have
other means of getting it.

I'd like to be able to use these channels in MythTV, but right now I
can't.  I've added the channels to my configuration.  However, when I
go to tune them I only get a partial lock, then I get the warning
message "You should have receive a lock....".  That's it; the channel
just stays in that partial lock state with a blank screen.  The signal
strength is consistently at 90% or better.  Outside of MythTV, using
mplayer I can watch these channels with a great picture and no
dropouts or anything like that.  I'm assuming the partial lock is due
to the lack of audio available.

Is there any way around this limitation within MythTV?