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Comment by philistine | Hacker News Reader

Some surprising companies have not completely figured out the correct way to use CEC either.

- Apple: When you start an Airplay stream on your phone directed at an Apple TV, the Apple TV doesn't send a switch input command.

- Nintendo: The Nintendo Switch switch input command when waking from sleep is unreliable at best.

- Microsoft: Surprisingly the worst offender. The only switch input command it ever sends is when it wakes from user-induced sleep. If you let the console go to sleep on its own, and wake up the controller and press the big Xbox button, it never sends a CEC command.

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Sony seem to get this right: My PS4 can turn on my TV and switch the input source when it wakes up, but is also clever enough not to do so if you wake the PS4 via remote play (where you are streaming the output to some other device)

However, I think that the issue is that CEC support has never been 100% reliable and interoperable. My TV is also made by Sony, which likely helps with compatibility. Probably all these devices work well with some TVs and not others, despite everything claiming to support CEC.

My PS5 will randomly steal the input from my LG TV's internal smart apps. My Nintendo Switch does whatever it feels like doing at random.

Frankly I find the technology to be a total mess, and there's no way to debug it.

The PS5<>LG interaction is fucked. The TV will wake up all its devices when one of them does, and the PS5 will grab the input even if it wasn't the initiator.

You can disable this in config, but it's all-or-nothing: now the PS5 can't wake the TV at all.

Attempting to report the misbehavior to LG and Sony is like shouting into the void. They don't care, or it's the other entity's problem, or both.

Exactly the same on PS5 <> Philips TV. Needed to turn it off completely.

Wow, sounds like a dream. I had it happen ONCE that my chromecast-with-googleTV did NOT turn on the TV screen when streaming spotify.

Also my xbox turns on the TV, but that never turns on the speaker bar.

Sony TV as well, I guess.

Apple: When you start an Airplay stream on your phone directed at an Apple TV, the Apple TV doesn't send a switch input command.

I think it depends on the equipment combination, and its state.

I'm able to send an Airplay stream to my AppleTV and it both turns on my LG television, and switches the input to the AppleTV.

However, if the TV is already on, and I send an Airplay stream to the TV it will not switch the input. Which I think is an OK measure if you have kids or roommates or the TV is in a public setting so that someone might hijack your viewing as a joke or to be annoying. My memory is that this used to be possible with an earlier model AppleTV, or an earlier version of iOS.

That said, ever since I attached a $23 no-name Chinese DVR to another HDMI input on the same LG TV, the AppleTV no longer has the ability to wake or change inputs. Very strange.

At least for my TV, which is some cheap Element Amazon TV from 2017, my Apple TV has full CEC. It will change input to Apple TV whenever I interact with it, and can turn the TV on directly. So it has to be how the TVs implement things. I've wiped my TV firmware back to 2017, so it's possible newer TVs intentionally break their CEC features to encourage you use their own (bad) smart features?

it's possible newer TVs intentionally break their CEC features to encourage you use their own (bad) smart features?

In my case, the TV is from 2015.

I know because my wife and I just happened to be in an electronics store when the Pope was visiting the United States in 2015, and it was on all of the televisions.

At the time, we had a 32-inch TV from 2003ish, and when my wife saw the Pope on the 65-inch screen in the store, she immediately grabbed a salesperson and said, "I want to see the Pope like that."

So, in case you've ever wondered if the programming on a TV in a store matters, the answer is "sometimes."

> - Apple: When you start an Airplay stream on your phone directed at an Apple TV, the Apple TV doesn't send a switch input command.

I have almost the opposite problem. Any time I turn on my TV and receiver to use another device (often my Nintendo Switch), the Apple TV somehow wakes up and then switches my receiver's input to itself. (My receiver is my HDMI switcher and has a single HDMI output to my TV.) This is a very annoying problem, and is the only reason I still need to have the receiver's remote nearby.

Another unrelated but incredibly annoying problem I have with this whole setup is that it's essentially impossible to play music through my receiver with my AppleTV without the TV being on. Turning off the TV will, of course, turn off the receiver too.

I have the same issue with my XBox: It gets turned on by the TV (without me wanting this), but fails to turn on or off the TV (which would actually be useful).

You can get a special HDMI cable with the CEC cables disconnected to stop that.

CEC won't work at all then of course, but it will fix that problem.

I've never seen a device that supported CEC where use of it wasn't toggled inside a menu. Both sides of the wire need to accept it.

I've seen millions of comments on AV forums from Apple TV users having problems with CEC.

I don't have an Apple TV. Does it have a setting to disable CEC?

TVs usually have an option to disable (i.e. ignore) it though, at least every one I've owned/helped someone with has.

I can disable CEC on the TV, but of course I want the TV to turn on when I wake up a device. I just want to be able to turn off the TV and have it not turn off the receiver. Picky, I know, but I gathered that we’re deep in “first world problems” here.

Sounds like there is a market for a CEC firewall box. Something $1 ESP8266 based you could configure with a phone/laptop over the air in visual way (webpage) to pick an d choose what can pass in what direction, maybe even with ability to add simple scripts triggered by particular messages. ~$5 BOM ~$15 retail.

I'd buy one.

> When you start an Airplay stream on your phone directed at an Apple TV, the Apple TV doesn't send a switch input command.

Oh? My Apple TV 4K (2021) turns on the TV and receiver when I start AirPlay, and the receiver switches the input to the AppleTV if it wasn't already on it. This works whether the TV+receiver were on or off. My TV is a Sharp from ~2013, and the receiver is a Yamaha also from around the same time.

I haven’t tested this enough to know if it’s a real hidden feature, or just me placebo-effecting myself, but I swear it takes way less time to wake up my TV (Samsung) if I press the little TV button on the ATV remote 5x really fast.

Like if I press it once, the ATV wakes up and usually the TV does, but often showing the wrong source. 5x fast consistently wakes the TV to the right input.

Google got it surprisingly well with the Chromecast with Google TV, it can send a power on and off, switch input and even control the actual TV volume through CEC.

I just wish it supported auto-off. It is nice that I can ask it to turn off the TV but I really don't need the screensaver playing forever.

I really like how starting a cast can wake up my whole A/V system.

Are you sure you didn't get bluffed out by their IR emitter?

Chromecast with Google TV contains an IR emitter to handle that, and IR is the default not CEC.

I can change the volume from another floor (I tried out of curiosity), and it also controls the TV volume through the Android TV Remote. My phone doesn't have an IR emitter.

People reading this, make sure to enable it in settings. Thought my TV didn't have HDMI-CEC, but it was deep in the settings and unchecked by default.

Some years ago I set to be able to control my smart TV via my laptop. Unfortunately, the graphics card (integrated or discrete) must also support the CEC spec in order to be able to send commands to the TV. Having a HDMI cable is not enough. My laptop did not ship with that requirement.

Also, I don’t know if it changed since I no more have a TV but on my last TV, HDMI CEC was both disabled by default but also renamed with some stupid marketing feature name TV manufacturers are capable of like SmartLink or some shit like this. BTW, it was a LG TV before WebOS.

Yes, some manufacturers give CEC a different name for added confusion; on LG sets it is called SimpLink. The Wikipedia page reports them.

https://en.wikipedia.org/wiki/Consumer_Electronics_Control

Yes ! Thank you ! It was SimpLink.

On the same topic, I once bought a vacuum cleaner on which they wrote on the box « ExtraRangePlus (R) TM: Up to 12m power cable length ». Just why !?

My Switch's CEC is as flaky as yours, but my Xbox One X does wake up the TV from sleep no worries even if I let it go to sleep, last I checked. Though now I really want to double check this, and see whether it's the Xbox that has messed it up, or the Xbox + TV manufacturer combo?

My Apple TV 4K wakes my TV and to the right input with Airplay though!

I solved the switch input issue by using an automatic HDMI switch from Aliexpress. This thing is remarkably reliable at switching to any source that starts emitting a signal.

I don’t know if there are switches capables of turning on and off the TV based on the presence or lack or signal but that could be the ultimate solution to this issue.

I hadn't noticed that with my Xbox, but then again I may actually have the sleep timeout turned off...

I'm surprised that they'd get it wrong though given that they've properly supported the HDMI VRR and ALLM features since the Xbox One X. (AFAIK Sony doesn't have either of those, even on the PS5. And with Nintendo it's surprising they have any CEC support at all)

What is the purpose anyway? Why would a device send a signal to turn on the tv through an HDMI connection, without tuning to that HDMI channel?

That seems to be the main use case, but instead the design forces every source to be a universal remote control.

I use my chromecast to turn my TV on or off with voice commands, even when I just want to watch FTA channels.

So you use your device as a universal remote control. That is not at all the common use case.

I mostly use it so that a 'goodnight' voice command will turn off the TV, no matter what source is selected or what is playing.

So it doesn’t matter at all if the tv switches to a channel or not.

When Apple TV sends my Samsung TV to "sleep", the TV doesn't fully turn off the display.

In a dark room, you can still see a dim glow coming from the LCD panel that only goes away if I press the power button on the Samsung remote.

:/ works great on my samsung serif as long as its plugged into the port labeled 'hdmi-cec'

Having worked on a large product that plugs into TVs and uses CEC, I wouldn't be so quick to blame the devices as I would be to blame your TV...

The Nintendo switch input command seems to work absolutely fine.

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