HDinMA said:
HD is another factor, but I think the buffer in and of itself is a bigger one. As I stated, the H21 is lightning fast compared to the HR21 even though both receive HD. I think Mpeg2 is faster as well, even though that seems illogical.
This is correct. I also have an H21 and it will do channel changes in less then a second, including all various HD formats and resolutions. Native On delays it a bit but not too much.
As I stated before, contrast an SD DirecTivo channel change to a standard receiver and you'll see the same issue. The DVR takes a good 1-2 seconds longer on a channel change simply because of the buffering on the hard drive.
Now add in HD and resolution changing and you're adding on more time.
Then add in HDMI issues with some TVs and I've seen some people up to 5-7 seconds for channel changes.
So eliminating as many of the issues in terms of HDMI and resolutions and native on/off can get you back down to near the standard DVR channel change time. And of course every single setup is different so there is no one "right" answer on what to do. It will be trial and error for everyone.
But no matter what you do it will never be as fast as a non DVR receiver.