Not sure about the HD PVR as I haven't confirmed its settings, but on the Nextbox 4K, the single best thing I did to improve video quality was:
Now, I know what you're thinking -- why would you pick 1080i, isn't it better to use 720p or 1080p, the "p" means they support a full resolution, full 60 frames per second, after all...
Well, according to previous forum posts, it used to be that some channels would broadcast in 1080i at 30 frames per second while others went 720p at 60 frames per second. But I have yet to find an HD channel that streams in 720p or 1080p on my box, let alone 60 frames per second. Even the sports channels I tried (again, not all of them), would stream in 1920x1080, interlaced, at 29.97 frames per second (which rounds up to 30 for shorthand).
Okay, so now you might be thinking: but if I set it to 1080p at 60 frames per second, doesn't that mean I'm getting every frame of your 1080i signal, just doubled or something? Sort of -- there's a conversion going on here, but it's not entirely from 30 to 60 frames per second. Instead, it's a de-interlacing, which means every two frames are combined into one frame by the processor in the Nextbox 4K.
Now, this sort of de-interlacing can be unnoticable, but from what I can tell, the box is *terrible* at it. Content can seem to flicker or get mushy; or will appear clear when nothing's happening, but edges or contrast might get slightly pixelated when there's a lot of motion. For more on de-interlacing, and why it's best to never convert interlaced footage to progressive, see Wikipedia or the examples of interlaced "blur" at http://www.onlinevideo.net/2011/05/learn-the-basics-of-deinterlacing-your-online-videos/
The best way to "de-interlace" footage is to show it on the big screen, and transmit it there in its raw, interlaced glory. And so, I have a feature suggestion: allow me to set the NextBox 4K to decode the MPEG2 frames with "passthrough" settings: to dynamically change resolutions and interlace settings based on the primary (full-screen) video being displayed.
Now, the default, which might currently be 720p, I would change to 1080i and encourage folks to keep it at that setting *until HEVC becomes more common and interlacing is dropped from channel signals* but it's even easier to have a setting that is called "dynamic - up to 1080p" or "dynamic - up to 1080i" and use the appropriate resolution on every channel change. A dynamic setting would also allow for easy switching from 4K to 1080i without having to go to the Settings menu every time, that said, maybe this is already possible? (I don't yet have a 4K TV.)
I'd also like to know why the 30 second skip forward button on my new RF remote control is not enabled when the skip back button obviously works.
Finally, why can't I plug in a USB key and backup my recording/PVR settings to it? Or transfer all recordings & settings to an external hard drive for easier replacement of PVRs? Obviously future IPTV PVRs will never need this -- I figure by then we should just have PVR functionality off-site in the cloud, and your "recordings" are nothing more than bookmarks on previously recorded and ready-to-stream content.
And one last thing -- any timeline for switching from poor MPEG2 encoding to something better like MPEG4 or HEVC in 1080p? I mean, yes, you can get some amazing results with MPEG2 1080i, but it makes hand-held footage of busy scenery look absolutely terrible. By comparison, HEVC dynamically adjusts how much data it encodes in each frame, which is horrendously complex, but indicates just how much better encoding has become since MPEG2 was state-of-the-art: https://sonnati.wordpress.com/2014/06/20/h265-part-i-technical-overview/
Need I remind folks that MPEG2 is what's used on DVDs? So if you've ever felt like your HDTV was playing back slightly more detailed DVDs, this is why -- why Blu-Ray, Netflix and YouTube all look nicer than most people's HDTV streams. For the best mix of compression and image quality, cinemas actually encode videos as a series of JPEG 2000 photos, for practically lossless encoding. That would be the opposite of MPEG2, or the sometimes mushy video we're stuck with currently.
But enough ranting from me. Any thoughts? Did 1080i improve things for you too? Try a few different video settings and see what you get. Pay close attention to sports channels or wildlife channels. Watch CP24 or other news channels and look at how smooth text might fade or appear. Also remember that your TV has picture settings that can interfere with the image -- smoothing or sharpening the image unexpectedly.
One last thing, in regards to image quality, on radX (and possibly other channels), I'm noticing that the ads inserted into the channel from Rogers look much nicer and clearer than the content it's been playing for hours. Is it possible that some channels are double- or triple-encoded while other sources, like ads, are encoded just the once for delivery over MPEG2?
With a nextbox 3.0 I agree, set it to 1080i output. You want the least amount of conversion as posible, and 99% of HD channels are brodcast in 1080i. (fox and abc are 720p). Rogers receives the hd stream in 1080i, then broadcasts it in 1080i, then the box outputs it to the tv in 1080i. This is the best setup since the only conversion is in the tv when it outputs to it's native res, which is usually 1080p.
However if you have a 4k Nextbox then I would assume you got it because you have a 4k tv that you spent good money on. In that case set it to UltraHD output, because setting it to any thing else (1080p, 1080i, 720p) is a waste since you arent getting the 4k resolution that you paid so much for. 4k Nextbox's should always be set to UltraHD output when connected to a 4k TV!
Also I doubt Rogers is changing from MPEG-2 or changing QAM settings, as they're going to launch X1 in 2018 as mentioned, so they're not going to waste resources on the current setup.
The old 8300HD PVRs did passthru resolution (changed the box's resolution based on the input).
People complained non stop that they didn't have an HD guide.
With NextBox 2.0 and the RTN guide, Rogers gave people an HD guide, but had to do it by fixing the displayed resolution.
...and now people are complaining.
In short, Rogers can never win.