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Discussion Starter · #1 ·
This may not be the best section for HDMI assistance, but I don't visit those other sections so I hope y'all don't mind.


I recently got a very nice 1080p projector and 110" screen, and upgraded to a Blu-ray player. Yeah, I know, welcome to 2008.



Anyway, in order to watch both the Blu-ray and cable TV I bought an HDMI switcher from Blue Jeans Cable. Everything works perfectly, even with 60' of wire from the switcher to the projector, except sometimes when I call up the on-screen cable guide and/or change channels, the signal drops out and does not come back until I switch to Blu-ray and back to cable TV again.


Blue Jeans support told me they doubt it's the 60' wire length because everything works perfectly otherwise. Of course, my cable company's support is useless.


My plan is to buy another brand HDMI switch to see what happens, and if that fixes it return the first switch. But before I do that I thought I'd run this problem past the experts here. I'm sending only video through the wire, and if you think it is the wire length I could buy a booster instead of a second switch to try.


Any advice is most appreciated.


--Ethan
 

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It's likely your cable box doesn't understand its obligations under the HDMI HDCP law.



Like many cable systems, the resolution used to display the channel guide is different than the resolution of the other channels. When you change resolutions out from under the HDMI gods, without properly EDID'ing yourself, they can get angry. When you switch back and forth between sources on your switch, it appears the switch is behaving and requesting the sources, sinks and other interested parties properly identify themselves (and their capabilities).
 

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Discussion Starter · #4 ·

Quote:
Originally Posted by skdmrklcy /forum/post/16921294


Did you try it with just the cable and no switch? I would almost guess that is a handshake issue with your cable box. I have had bad luck with cable boxes and HDMI though.

I did try that, but the cable box seemed unable to drive the long wire because the video kept flashing on and off.

Quote:
Originally Posted by Dennis Erskine /forum/post/16922067


It's likely your cable box doesn't understand its obligations under the HDMI HDCP law.

I was afraid of that, because I'm sure Charter Cable and Scientific Atlantic will not offer to fix this.

Quote:
the resolution used to display the channel guide is different than the resolution of the other channels.

By George, I think you nailed it. This also explains why the problem is intermittent. I watch mainly HD channels, and you are correct that the guide is not in HD. So that makes perfect sense, even if it doesn't solve my problem. Thanks Dennis!


--Ethan
 

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We deal with Charter a lot but more in northern, CT and Mass. The problem you are having is common with certain equipment. Usually, we prefer to send the native signal to the display as its video processing is typically better than the cable box. But, in cases lke this reliability takes precedence. Set your cable box to only 1080i or 720P depending which had more of your favorite channels.


In our area you do this with the power off (not unplugged just off). Press 'guide' and 'info' at the same time on the front of the cable box. It may take a few times. It will bring up a set up menu and give you an easy option or an advanced option, I forget what they actually call it. Choose the advanced option. It will show you a resolution and ask if you want to select it or not. Go through so you only have one resolution showing which ever you decided. Once the cable box is doing all the processing you won't have the problem with the guide or going between channels of different resolution.


Hope this helps.


Bob
 

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Quote:
Originally Posted by Ethan Winer /forum/post/16921174


This may not be the best section for HDMI assistance, but I don't visit those other sections so I hope y'all don't mind.


I recently got a very nice 1080p projector and 110" screen, and upgraded to a Blu-ray player. Yeah, I know, welcome to 2008.



Anyway, in order to watch both the Blu-ray and cable TV I bought an HDMI switcher from Blue Jeans Cable. Everything works perfectly, even with 60' of wire from the switcher to the projector, except sometimes when I call up the on-screen cable guide and/or change channels, the signal drops out and does not come back until I switch to Blu-ray and back to cable TV again.


Blue Jeans support told me they doubt it's the 60' wire length because everything works perfectly otherwise. Of course, my cable company's support is useless.


My plan is to buy another brand HDMI switch to see what happens, and if that fixes it return the first switch. But before I do that I thought I'd run this problem past the experts here. I'm sending only video through the wire, and if you think it is the wire length I could buy a booster instead of a second switch to try.


Any advice is most appreciated.

60' is a lot of length for HDMI. Usually, you need some kind of high tech cable with boosters or lots of insulation and copper to go that far.


I've been working with HDMI and DVI (basically HDMI over a physically larger connector with no sound) for about a year, and found that failures like this can happen with functionally inadequate cables.


The problem you are describing is what I'd call video pattern sensitivity. IOW some patterns of video cause no problems, and others do cause problems.


I've played around with different sources and different loads (mostly large LCD computer displays but its really all the same) and found that all three things can matter. IOW you can have a cable and display that will work with some sources, and not others. The same for displays.


This seems like very-undigital behavior, but I believe that the source of the problem is actually the same in every failing case - a system that is simply just to close to the edge to be totally reliable with all signals, sources, and loads.


Your digital dividend is not that systems always totally work or always totally don't, but rather than when one fails, the failures are pretty gross. It's not like the colors are subtly wrong or the brightness is off, but rather that the display is basically going bananas.
 

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Quote:
Originally Posted by Ethan Winer /forum/post/16921174


.

My plan is to buy another brand HDMI switch to see what happens, and if that fixes it return the first switch. But before I do that I thought I'd run this problem past the experts here. I'm sending only video through the wire, and if you think it is the wire length I could buy a booster instead of a second switch to try.


Any advice is most appreciated.


--Ethan

Ethan-


I can lend you another switch next weekend if you would like to try it.


Kal
 

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Discussion Starter · #9 ·

Quote:
Originally Posted by BobL /forum/post/16927621


Press 'guide' and 'info' at the same time on the front of the cable box ... Go through so you only have one resolution showing which ever you decided.

As it happens I found and downloaded the "advanced" manuals for my box, and I saw the cable installer guy go through that when he brought this box. So I will try that. Thanks! I figured I was stuck with this problem, and now there's hope again. I'll let you know what happens in the next day or two.


@Arnie: I'm pretty sure the cable length is not the problem because switching to the guide, and between HD to SD channels, is the only time this happens.


@ Kal: Thanks much for the offer. If Bob's advice doesn't fix it I'll email you to arrange the borrowing.


--Ethan
 

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That is what your box "Should do". From my experience, "should do" and "will do" are rather different things, especially when it comes to SA cable boxes. The projector also "should" recognize resolution switches and respond accordingly. There hardly would be a market for all those nifty Gefen gadgets if HDMI devices interfaced the way they should...


My own HTPC setup, btw, started functioning the way it "should" only after I added a $100 Gefen box...
 

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I can't believe you got rid of your beloved RCA B&W box Ethan
 

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Quote:
Originally Posted by Dennis Erskine /forum/post/16922067


Like many cable systems, the resolution used to display the channel guide is different than the resolution of the other channels.

Maybe, but this is not how my DirecTV box works. Judging from appearance, the channel guide graphics probably are always the same VGA resolution, but the guide must sometimes be upconverted, because it is displayed at the resolution of the last channel viewed -- 480i, 720p, or 1080i. So although changing channels may change the signal format, bringing up the channel guide never does.
 

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Quote:
Originally Posted by GregLee /forum/post/16944780


Maybe, but this is not how my DirecTV box works. Judging from appearance, the channel guide graphics probably are always the same VGA resolution, but the guide must sometimes be upconverted, because it is displayed at the resolution of the last channel viewed -- 480i, 720p, or 1080i. So although changing channels may change the signal format, bringing up the channel guide never does.

I live in the same town as does Ethan and, probably, have the same cable box. With a fixed resolution set on the box, I do not have the problem that Ethan has even when I had a switchbox.
 

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Discussion Starter · #16 ·

Quote:
Originally Posted by BobL /forum/post/16927621


Set your cable box to only 1080i or 720P depending which had more of your favorite channels.

I tried that last night, setting the box so 1080i is the only output option, and it still goes nuts and loses the video half the time.


I'm borrowing a known-good switcher from Kal this weekend, so hopefully that will tell me for sure who's the culprit.


--Ethan
 

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Quote:
Originally Posted by Ethan Winer /forum/post/16988686


Just to follow up on this, Kal Rubinson was nice enough to loan me an HDMI switch and that solved the problem. So this proves it was the switch after all.


Thanks Kal!


--Ethan

****. That means I don't get it back.
 
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