HDMI connections disrupt channel changes

[mod]

Hopefully someone here has seen this and knows why it happens. I have a Panasonic plasma, RXV663 receiver, and a cable box. When I had it all connected with component cables all worked well and a simple TV channel change would simply change one channel to another. I've now switched to HDMI for all connections and when I change channels the TV flashes the picture of the new channel for a split second, then the screen goes to black and in the top left corner of the screen shows HDMI2 for a second or two, then the picture comes back. Talk about irritating! Any ideas?

 

[TLS Guy]

Hopefully someone here has seen this and knows why it happens. I have a Panasonic plasma, RXV663 receiver, and a cable box. When I had it all connected with component cables all worked well and a simple TV channel change would simply change one channel to another. I've now switched to HDMI for all connections and when I change channels the TV flashes the picture of the new channel for a split second, then the screen goes to black and in the top left corner of the screen shows HDMI2 for a second or two, then the picture comes back. Talk about irritating! Any ideas?

That's HDMI making the required HDCP handshakes. However yours is on the slow side. I would try a better quality HDMI cable. It looks as if you are at version 1.2. Make sure you have a good cable rated at 1.2 or higher.

Get your cables here. Especially avoid Monster and other junk sold at Worst Buy.

 

[mod]

I bought the HDMI's at monoprice.com and they say they are 1.3a rated. Before I buy other hdmi cables, is that the only thing that would cause this?

 

[mod]

About the handshake issue, which hdmi connection would be the most critical? From the TV to the receiver, or from the cable box to the receiver? I know they're all important, but could changing just one particular cable to a better hdmi cable fix the problem?

 

[TLS Guy]

About the handshake issue, which hdmi connection would be the most critical? From the TV to the receiver, or from the cable box to the receiver? I know they're all important, but could changing just one particular cable to a better hdmi cable fix the problem?

You cable should be fine, unless you happen to have a bad one.

The cable box to receiver, is a connection that is required to make continuous handshakes, so called repeater architecture. The TV being a a display which is considered an end device, is required to make one initial HDCP handshake.

From the information you have provided, of I had to make a guess, I would say your cable box most likely has a cheap and slow microprocessor chip. Not unusual.

One other thing, if there is up converting to be done, have your TV do it and not the receiver. Also make sure your cable box is outputting at the highest native resolution of you TV, not higher or lower. If your cable box has a lower resolution than your TV, have the TV do the up convert.

This will speed things up. However I'm pessimistic, that this problem is solvable

 

[mod]

OK, I checked the resolution setting and that's OK. I then switched back to component cables from TV to receiver and cable box to receiver. With this setup, most channel changes go pretty well in that the new picture comes up while also showing Comp2 in the upper left corner for a second to indicate the input I guess. However, on some channel changes the picture kind of flutters quickly a couple of times like it's trying to do the handshake. It's much faster this way than with hdmi though. I wonder if the Time Warner has a faster cable box available. Or would they even know!

 

[TLS Guy]

OK, I checked the resolution setting and that's OK. I then switched back to component cables from TV to receiver and cable box to receiver. With this setup, most channel changes go pretty well in that the new picture comes up while also showing Comp2 in the upper left corner for a second to indicate the input I guess. However, on some channel changes the picture kind of flutters quickly a couple of times like it's trying to do the handshake. It's much faster this way than with hdmi though. I wonder if the Time Warner has a faster cable box available. Or would they even know!

There are no handshakes with a component video connection. So if there are still issues with that connection it is the cable box.

You should get the best picture quality with HDMI, because it is saving a conversion from analog to digital.

I would really get after Time Warner. After working through this, it looks as if it is their issue.

 

[mod]

I just googled the Atlanta Scientific 4250hdc cable box and found loads of folks having problems with it.

Some newer HDTV's have their own decoder to eliminate a cable box. For those of us without a built in decoder, is there a decoder we can get to not have to use the cable boxes? It seems like I'm having to pay $6 a month to rent that box from TW.

 

[TLS Guy]

I just googled the Atlanta Scientific 4250hdc cable box and found loads of folks having problems with it.

Some newer HDTV's have their own decoder to eliminate a cable box. For those of us without a built in decoder, is there a decoder we can get to not have to use the cable boxes? It seems like I'm having to pay $6 a month to rent that box from TW.

Well one digital TV tuner should be the same as another, however due to incompetence, self interest or both, it appears to be not necessarily so.

That is why I'm very interested to see if the Comcast box solves the OPs problem, in this thread.

http://forums.audioholics.com/forums/showthread.php?p=493417#post493417

If it does, then there are two possibilities.

1). The OP's TV has a lousy digital cable tuner.

2). The signal sent out by Comcast is not adhering to the rules, because of incompetence or self interest.

Obviously only the cable company stands to gain financially from this problem.

Unfortunately if the cable box solves the OP's synch problem, we still will not know which of 1 or 2 above are correct. That is what makes this whole area so difficult, and the cable companies can hide behind it.

Obviously ones first suspicions lie in the direction of the cable company.

You can certainly buy digital cable tuners by the way, if you want.