If you are using Ethernet cable, check for any setting to DISABLE the WiFi on the TV, or options like screen casting or mirroring. You can use an app like "WiFi Analyzer" to check the WiFi around you to see if it's transmitting some signal that is mangling your network.

App updated, interestingly, to what looks like an old version before the update that broke everything. Selection captions and descriptions are now again legible on a 30" screen and old shows seem to play without issue. I've only played two old hour-long shows, but they've been without problem....

Many PBS stations sold their broadcast licenses in the recent FCC auction and are going off the air. Are any of them actually going off the air? "Many" of them? I had the impression that some PBS stations chose to sell their bandwidth and become subchannels on a partnering commercial stat...

PBS's money is getting tight. The current administration wants to end all funding. Many PBS stations sold their broadcast licenses in the recent FCC auction and are going off the air.

AMC and ESPN generally have their own apps that require logging into your TV service provider for authentication. If they are for 'free' on some Roku channel, they are almost certainly pirated.

The remote code setup for my JP1x-based remote shows this in the setup.

Not sure if this was mentioned, but AHC and Velocity are now available on Roku. BUT, if you are a Comcast/Xfinity user, you can't authorize. If you click on XFINITY, you get {"code":400,"message":"Invalid Request","description":"Invalid and\/or malformed ...

There is a story about the Roku NASA app on the Consumerist website:
https://consumerist.com/2017/08/21/the-nasa-channel-app-on-roku-doesnt-work-and-it-isnt-from-nasa/

The main note in the story is that NASA TV is a channel on Pluto TV, which is a Roku app that works.

Are you sure it was the real PBS app? Maybe there is some fake PBS-looking app that was accidentally installed?

On the DSLReports forums, there is a thread that the DiscoveryGo (and related TLC Go, ID Go, etc....) all have very low resolutions when playing on Roku's. These are all Comcast customers. Has anyone else noticed this on Comcast or other ISP's? I haven't had a chance to check it out personally yet. ...

I installed and activated the app with my Comcast/Xfinity account with no issues.

The Roku boxes can also be controlled by a phone/tablet app. Are you sure somebody isn't messing around with the app?

As others mentioned, that speed listed on that mini-diagnostics is just the average bitrate of the video itself. Netflix does incredible things with compression without affecting the picture all that much (now if only they could teach Comcast how to do that...) There is also a Netflix speed test, bu...

I don't know what the spammers think when they make it look so obvious. Shows just how brain dead they are, or how stupid some users would be to actually click on those blatantly fake links. 

This is probably better asked on the Roku Developer Forums:
https://forums.roku.com/viewforum.php?f=34