SageTV Inducing Stream Errors?

[Taddeusz]

Not that anything can really be done about this if this is indeed the case but thought I'd post something anyway.

To give a little background I've had issues with stream errors on and off with my HDHR's for quite some time. Kind of came to a head last week when I discovered that I actually had a bad network cable running to my SageTV machine. First time I've had an actual bad cable, but anyway.

The problem is that I'm still getting the odd error in my recordings here and there. It's not really consistent by channel. Sometimes there are more than at other times.

I've done testing outside of SageTV with all 4 HDHR tuners simultaneously using the command-line utility hdhomerun_config.exe. I get few to no errors on those tests when I run the files through VideoReDo compared to recordings through SageTV. The few errors I do manage to get are confined to a single channel.

I have even conducted 2 other tests where on the first I was simultaneously running comskip live on all 4 at the same time and on the other I started Plex transcoding video to sync as well as running comskip in order to really load the processor. The results from both of those tests were identical to the "no load" test.

I'm at a loss to figure out where I'm getting the errors from. It just doesn't make sense that I'm getting no errors during the day and then notably more errors during "prime time". I'm thinking about putting a pre-amp on my antenna just in case I have too high of loss from my cable run in combination to my distance from the transmitters. According to AntennaWeb I'm in the yellow to red zones as far as reception is concerned.

My antenna is an RCA ANT751 installed in the attic with about a 30ft run of RG6 to a 3-way splitter to feed the 2 HDHR's. It is aimed in the general direction of most of the transmitters, not very precisely. Signal strength and quality are very high.

Really just throwing this out here. If anyone has any suggestions it would be great. I think I'll go ahead and get a pre-amp since they are fairly inexpensive.

[routerunner]

Originally Posted by Taddeusz

The problem is that I'm still getting the odd error in my recordings here and there. It's not really consistent by channel. Sometimes there are more than at other times.

Different channels stream at different bitrate and at different time of the day, in short, higher the bitrate and higher are the chances of error in the data stream, so inconsistency is pretty normal.

I've done testing outside of SageTV with all 4 HDHR tuners simultaneously using the command-line utility hdhomerun_config.exe. I get few to no errors on those tests when I run the files through VideoReDo compared to recordings through SageTV. The few errors I do manage to get are confined to a single channel.

I'll suggest to stick all your tests to the channel that consistently shows the issue and try to discriminate between a network error or a signal problem. Run a Wireshark on the network node to finally discriminate between the two.

I'm thinking about putting a pre-amp on my antenna just in case I have too high of loss from my cable run in combination to my distance from the transmitters. According to AntennaWeb I'm in the yellow to red zones as far as reception is concerned.

My antenna is an RCA ANT751 installed in the attic with about a 30ft run of RG6 to a 3-way splitter to feed the 2 HDHR's. It is aimed in the general direction of most of the transmitters, not very precisely. Signal strength and quality are very high.

Where and how you measured the signal strength/quality? At the antenna or HDHR point? Signal loss through coaxial cable depends on length and frequency. The longer the length of coaxial cable, the more signal is lost. The higher the frequency of the signal passing through the coaxial cable, the higher the loss over a given length, also every junction/connection point reduces the signal further of about 3dB. If you are measuring the signal at the HDHR side and still, as you mentioned, the strength/quality is very high then a pre-amp wouldn't do anything to you, quite the opposite in fact, it might burn your HDHR inputs, so proceed with caution as I'm not sure how much signal power the HDHR can tolerate.

Hope it helps
Eddy

[trallyus]

I had issues with my recordings using the default sage tv encoder giving me playback errors with artifacts in my recordings until I switched to the nvidia platinum encoders I bought to go along with my nvida card and it worked wonders.

If your still using the default encoders making a simple switch like trying different encoders really helped me out.

Not sure why it made a difference but it did.

[Taddeusz]

Originally Posted by trallyus

I had issues with my recordings using the default sage tv encoder giving me playback errors with artifacts in my recordings until I switched to the nvidia platinum encoders I bought to go along with my nvida card and it worked wonders.

If your still using the default encoders making a simple switch like trying different encoders really helped me out.

Not sure why it made a difference but it did.

Not sure how that would help. I have a headless server and am using media extenders for all playback. The server does no decoding.

[trallyus]

Originally Posted by Taddeusz

Not sure how that would help. I have a headless server and am using media extenders for all playback. The server does no decoding.

I am using my sage tv on my pc so that is why if helped my recordings. had a brain fart for a moment there and forgot that HDHR's were those HD HomeRun tuners - sorry for about that

[Taddeusz]

Well, I started testing this morning with the 2 "problem" channels that I seem to have. Left it running. When I came back to my remote session I noticed a whole lot of network errors. Did some research and as I'm running Windows 8.1 I went in and disabled the network throttling. Started another testing session. We'll see how this goes and how tonight's recordings fair.

[Taddeusz]

Still getting lots of network errors. Looks like my switch is getting swapped back out tonight.

[Taddeusz]

Well, I changed out the switch night before last and am still getting the network errors. Looks like a new motherboard is in my future. I've been eyeing a Supermicro X7SBE as a drop-in replacement for my current LGA 775 board.

With the problems I've had with boot ROM's on my current and supposed replacement boards I've decided I need to stick with real server boards for this stuff. Otherwise I would just toss in another NIC. But alas the board won't boot with both my SAS card and an add-on NIC. Very weird. I had the same problem with the other board I was attempting to use.

[Taddeusz]

Weird, just did another test this morning and got zero errors. I hate these intermittent problems.

[routerunner]

Originally Posted by Taddeusz

Weird, just did another test this morning and got zero errors. I hate these intermittent problems.

You said that in the evenings you mostly have errors and not in the mornings so it looks like that your results are consistent? How did you checked for network errors? Did you use Wireshark as suggested? With that tool you can finally discriminate between network vs aerial issues.

Eddy

[Taddeusz]

Originally Posted by routerunner

You said that in the evenings you mostly have errors and not in the mornings so it looks like that your results are consistent? How did you checked for network errors? Did you use Wireshark as suggested? With that tool you can finally discriminate between network vs aerial issues.

Eddy

The hdhomerun_config.exe utility determines the type of error. It displays a "." for normal, "t" for transport, "n" for network, and "s" for sequence errors. I haven't tried Wireshark yet.

[Taddeusz]

One of the reasons why I tend toward this being a bad motherboard is that it has developed at least one bad capacitor. You'd think Intel would have used quality caps on their motherboards, but apparently not. Just a matter of timing to get the money together to get the "new" board.

[Taddeusz]

Ok, after a motherboard replacement I believe I have found the root of the problem. The replacement board I ended up with is an Intel DP43TF. Essentially the same board I already had but without the integrated video.

Got it all switched over and was still getting random network errors that spanned all four tuners on both HDHR's at the same time. I spent the better part of a couple hours tweaking the NIC settings trying to get the network errors to go away. This morning I decided to stick in a PCIe Intel NIC that I had laying around. I didn't think it would work since the other board would not boot when I got more than one bootable card installed. Remember, I have a SAS card. But it worked this time!

So I was doing testing and was still getting the occasional network error. Tweaked the receive buffers and don't seem to be getting any network errors. I'll keep an eye on it but it appears that I have figured out that the Intel integrated NIC on these 4 series boards does not seem to get along with the HDHR at all. At least not under Windows 8.1 with the Microsoft drivers (no Intel drivers are available). The add-on NIC is actually using the Intel drivers.

[Taddeusz]

As a side note, I believe I've also solved a non-critical issue that I've been having for as long as I can remember. I've had an issue where I'll be using the smooth FF and REW on my media extenders and it will all of a sudden make a huge jump.

In my quest to solve my HDHR recording issues I came to better understand one of the NIC settings, Interrupt Moderation/Mitigation. In short, this setting essentially attempts to lump network transmit or receive frames together into a single interrupt rather than creating an interrupt for each frame that is sent or received. While this is good in that the CPU will be less burdened by processing interrupt requests, the result is that the timeliness of network traffic can be slightly affected. Since FF and REW are such a time bound processes I can only guess that interrupt moderation can cause issues such that I was seeing.

Since I disabled interrupt moderation I have not seen the sudden jumps that I was previously experiencing while using the smooth FF and REW. Only time will really tell but this one setting appears to have solved this issue.