First on TV #1, the signal is going through the receiver and when you change channels on the cable box, the signal needs to be routed through the receive which is causing a delay. Not totally sure about this.
Try this on TV #1: Try connecting the cable box directly to the TV, then plug the TV's Audio Out connection to the receiver. Your TV's audio-out may be either optical or RCA-type. At least this will give a direct connection between your cable box and your TV, but you will still get TV audio to your receiver.
I have television service through a cable provider. Each of my five TVs receives signal thru either an HD or SD cable box. They are set up as follows:
1) 46" Panasonic Viera plasma HDTV, about 1 year old. TV signal comes into a HD cable box, which feeds to a Denon receiver using a HDMI cable. A DVD player also feeds to the receiver via HDMI cable, and a single HDMI cable is used to transfer cable TV and DVD signals to the TV.
2) 42" Panasonic Viera plasma HDTV, about 3 years old. TV signal comes into an HD cable box and signal is fed directly to the TV via HDMI cable. There are no other devices connected to this system.
3) 20" Samsung LCD TV, about 5 years old, is standard def but is connected to a HD cable box via component cable. No other devices are connected to this system.
4) 20" Philips CRT standard def, about 2 years old, connected to a standard cable box via component cable. A DVD/VHS player is also connected to this system.
5) 32" Panasonic CRT standard def, about 15 years old, connected to a standard cable box via component cable. No other devices are connected to this system.
My problem is with TV #1. Channel changing takes a good 5 seconds, sometimes more, for some HD channels to show the video (the audio comes on quickly thru the external speakers). I notice that all of the TVs connected to an HD cable box take longer to change channels than the SD boxes, but TV #1 takes the longest (but only for some HD channels). I'm assuming that's because the signal is going through the receiver, but I don't know why only some channels are affected. (Both TVs with the SD cable boxes change channels quickly, regardless of what other devices are connected).
But the real problem with TV #1 is that the video signal too often does not reach the TV when viewing an HD channel. (The audio signal makes it to the external speakers, so I can hear the program, but not see it). I have to change to an SD channel to get a picture, then change back to my HD channel of choice. That usually works, but it's awfully inconvenient and frustrating, especially when viewing a crucial part of a program.
Another thing that happens is that while viewing an HD channel the video will cut in and out. I have to follow the same procedure as above.
This does not happen with any other TV. I spoke to Panasonic and they say that the TV sometimes apparently does not know what to do with the video signal coming from the receiver (but they can't say why that is). The cable people never give any direct response to my question...just that they'll "send a tech out", which never results in a fix.
I haven't spoken to the Denon people, but it occurs to me that the DVD player, which feeds thru the receiver just as the cable box does, never presents this problem.
If anyone has any thoughts, I'd love to hear them.