Ack! My STB is messing up my HDHR!

[tomfisk]

I've made a lot of changes to my Sage system recently. Built a new server, added an HD STB (DCH-6200) and threw an HD-PVR in the mix (although not currently used since I'm doing my recording from the STB with firewire).

I noticed that my HD content off my HDHR had occasional "glitches" in it (missed frames mostly) and in some cases was bad enough to cause a couple of recordings to stop playing back.

So...I figured in all the mucking I did that a coax went bad. I used the command line hdhomerun_config utility to tune the HDHR to a couple of different channels and then used it to save both tuners to "null". This shows if there are any problems in the network or reception. I also brought up the HDHR config GUI to watch the signal strength, signal quality, and symbol quality.

Then I systematically started checking cables. Everything was perfect, absolutely no errors until I hooked up the STB. Then, about every 30-60 seconds I get transmission errors (an initial error followed about 5 seconds later by 2 more) that blows the symbol quality to 0. I assume this is what is messing up my HDHR recordings.

I've replace the cable going to the STB. Even tried to isolate the STB's coax by running it through a surge suppressor. No luck...

All cable connections are coming off a powered 8 port amplifier with the unused ports capped with 75-ohm plugs.

Has anybody else seen this problem...know how to correct it?

[sic0048]

I'm guessing here, but is the box sending back two way signals back down the coax? Perhaps that is causing issues. Can you try adding a splitter between the amp/splitter and STB. Make sure you use a splitter that isn't rated for two way communications. That would cut out the communication and allow you to test the theory. Again - this is my grasping at straws because I've never seen anything like that on my setup.

[tomfisk]

After more mucking about, the STB is also pausing at the same time and mucking with the clear QAM on my HDTV. So...I've called Charter and the technician is going to show up on Sunday afternoon (I'm impressed that they work on Sunday!) Now to deinstall the STB from my server location and hook it up to the HDTV...

[evilpenguin]

Yep, I think you nailed it, it sounds like a badly misbehaving STB. Even when it does transmit, its never supposed to interfere with the downstream frequencies (55 Mhz+).

Don't let the cable guy leave without giving you a new one because if your STB is sending out downstream interference then its probably messing up a lot more than just your HDHR, it could be messing up your entire neighborhoods internet/TV (seriously).