[mythtv-users] Poor recording of races only

[Yippee Three-eight]

I've finally gotten my Ceton InfiniTV 4 PCie working on Mythbuntu.  <YAY!>  Anyway, I've set up a bunch of shows to record, all of them HD.  Many of those shows record just fine.  However, I'm a racing fan, and every race I've recorded so far has been of really poor quality except one.

All of those recordings show up with a yellow border.  I think that means the recording is damaged from what I've read.  When I watch the recording, every time a scene changes, the screen gets very blocky (macroblocking?) and the audio cuts out, then it will return to a beautiful recording for a moment until the camera changes, then it repeats.  It gets worse and worse as the show goes.  I haven't let it run, but I have noticed that the file size is very small.  For example, a normal TV show recorded for 1 hour at 5.xx Gb.  A formula 1 race (3 hours) recorded at 0.5 Gb.
I've also had some problems with BBC America.  Some recordings are great.  Some show up as yellow like the races.  Of those, some just hang the frontend.  Others come back with a message saying the file is missing.

The one race recording I recorded without problem was a NASCAR race that was not scheduled to record, but I turned it on in Live TV.  It looked great, so I went back to the program guide and tried recording it.  It recorded fine.  As I said, these shows are all HD.
 Initially, I was unable to record anything when I set up the box.  I was getting buffer errors.  I found that my network was running at 10Mb/s.  I fixed that so it's running at 1000MB/s, but I still have some Cat5 (not 5e) cable in the walls.
I looked at the channels that I've recorded on and here's what I got for signal strength and S/N ratio:TNTHD - always good:  Signal Strength - 3.8 dBmV, Signal to Noise Ratio - 32.6 dBWMAQHD - always good:  Signal Strength - 4.1 dBmV, Signal to Noise Ratio - 33.4 dBWBBMHD - always good:  Signal Strength - 5.9 dBmV, Signal to Noise Ratio - 34.6 dB
BBCAHD - sometimes good recordings, other times not:  Signal Strength:  2.3 dBmV, Signal to Noise Ratio:  34.1 dBNBCS1HD - always bad:  Signal Strength - 3.9 dBmV, Signal to Noise Ratio - 34.8 dBFS1HD - always bad:  Signal Strength - 3.5 dBmV, Signal to Noise Ratio - 32.1 dB
Since it seems like a channel thing (higher channels have problems, lower channels don't), I figured I'd look at improving my signal strength.  I've had a Motorola 1-2 amplified splitter (http://www.amazon.com/Motorola-Signal-Booster-BDA-S2-Amplifier/dp/B0017I1PVC/ref=pd_sim_e_5?ie=UTF8&refRID=0REJCWJTGHQ0WF945342) on the line coming into my house for a while now.  It helped a lot as before I couldn't tune.  I've got one of those lines going to my old STB, and the other going to a 1-2 splitter.  From the splitter, one line goes to the cable modem, and the other line goes to my backend's cable tuner card.  I've always read that splitters degrade signal, so I tried disconnecting the STB and connecting one long line directly from the Motorola amplifier to my cable card.  On all channels, SS goes up by 2 - 3 and S/N goes up a bit too.  I've read that a perfect signal strength would be 0 dBmV, but I'm wondering if that's wrong.
Can anybody offer any suggestions on what I should look at to be able to record these shows?
Mike

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