Why is my TV acting weird?

July 13, 2020 3:42 PM

My TV's ability to switch inputs is...fragile. Is this a thing?

We have a Sony TV that's about seven, maybe eight years old. It's still functioning pretty well - picture's still as good as I'd expect, sound is solid (we use a Sonos Playbase primarily, but I tested the sound from the TV yesterday, and it's fine). But in the last few months, when I switch inputs on the TV from "cable" to "Roku", that switch often results in nothing but a black screen.

Sometimes, I can resolve it by switching inputs again, then switching back, but sometimes I have to shut down and restart the TV in order to get it to work. This behavior isn't consistent, it doesn't happen every time, but it's starting to happen enough that I'm wondering if that's the first domino to fall in "you need a new TV".

I don't want to buy a new TV if I don't have to, so I was hoping to troubleshoot a bit. I have:

- one HDMI port dedicated to the cable box (Comcast X1, if that matters)
- one HDMI port dedicated to a Roku
- Optical audio out dedicated to the Sonos

All the cables in those ports are less than a year old.

I'm not looking to move away from this setup - I just want to understand what's failing on my TV. It's a smart(ish - it has Netflix and a couple other things, but we typically don't have it connected to the internet) TV, and I updated the firmware a week or so ago, but this problem predates that.

posted by pdb to Technology (8 answers total)

It does seem like it's not recognizing that the Roku is there and turned on.

I think it's slightly more likely that your Roku is failing than the TV. Or a recent Roku update introduced a bug. I'd check with them first.
posted by kindall at 3:46 PM on July 13, 2020

Response by poster: kindall:

Not to threadsit, but to clarify: the black screen happens when switching in either direction - from cable to Roku, or from Roku to cable. Roku is also only a couple years old and on most current firmware. I'll check into bugs on that side though.
posted by pdb at 3:50 PM on July 13, 2020

Best answer: I also have a Sony that's older than that, and it does the same thing and has for a while. I honestly don't remember how long, years at least.

So I wouldn't take this as evidence that your TV is on the verge of death or anything.

IIRC (I've changed the set up a few times over the years) it has a tendency to do this more often when starting on an HDMI input than component or antenna or other inputs. I believe HDMI has some kind of "handshake" between 2 devices that's connected with DRM/anti-piracy requirements, so my top-of-the-head assumption is that Sonys don't always get that handshake right in a timely manner, leading to black screen.

Very occasionally with my own Roku if I just wait for a couple minutes the picture will kick on. But yeah I just do a TV restart mostly. A little annoying but again for me so far no other problems, not a sign of imminent failure.
posted by soundguy99 at 4:13 PM on July 13, 2020 [1 favorite]

Best answer: Yeah, the HDMI handshake process is probably going slightly wrong, possibly because as the tv gets older it might react slightly slower or faster than it did before, meaning it misses some timing window and ends up with a black screen. This is indeed very common

You could try using an external HDMI switcher to flip between your inputs instead of two ports on the TV. Switches are very cheap and if only one of your ports is having issues you could put both devices on the good port and switch as needed.
posted by JZig at 4:21 PM on July 13, 2020 [1 favorite]

Some of the HDMI ports failed on my parents' old Sony, so it's definitely a thing that can happen.
posted by sevenyearlurk at 8:32 PM on July 13, 2020

I have a Roku HDMI widget that doesn't always connect. I think it's the wifi embedded in it. if your builtin Roku stops working, you could probably get a plug-in one.
posted by theora55 at 9:05 PM on July 13, 2020

I might try a different HDMI cable if you haven't already. And maybe some compressed air in the HDMI input. (Or, y'know, the old Nintendo cartridge trick of just blowing in it.)
posted by nosila at 11:04 AM on July 14, 2020

If you swap HDMI cables - which you didn't indicate you had, does the problem follow the port or the cable? While an untouched cable generally doesn't break - I used to swap a cable between devices all the time and it resulted in the cable looking good but its integrity going. I've had a Sony TV that is likely *very* similar to yours, and while it is older - it still has functional HDMI ports - and I'be burned through about 5 cables because I've swapped inputs.
posted by Nanukthedog at 11:35 AM on July 14, 2020