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Logitech MX Products are incompatible with AirPods

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Re: Logitech MX Products are incompatible with AirPods

#241

I would like someone who is having this problem to look at the 2.4 ghz band with an SDR. My initial untested hypothesis is the transmit power of the airpods can't handle the frequency competition of a peripheral device that is most likely way closer to the computer than the airpods.

With the conflicting experiences in these threads I wonder if there's an unknown third component that's influencing this problem. Some other interference causing Logitech hardware to switch bands or causing Bluetooth devices to use different connection properties, for example.

It doesn't take all that much interference to get a multi device Bluetooth piconet to see disturbance, perhaps a combination of interference sources is causing the Bluetooth performance on some Bluetooth adapter to fall back to lower speeds, ruining the experience for devices relying on high throughput Bluetooth.

Re: Logitech MX Products are incompatible with AirPods

#242

I like my MX mouse though I wish I could customize the buttons better without installing their software. There’s something about their software that makes me feel like it is going to spy on me and use all my computers resources. Their craft keyboard also looks super nice, although I can’t imagine the wheel being useful without their software running. I like flat keyboards. I don’t game. Who else makes premium stuff i…

Keychron and Nuphy make wireless bluetooth low profile keyboards. I own Nuphy Air 75 and really like it.

Re: Logitech MX Products are incompatible with AirPods

#244

Earlier quoted context omitted.

The whole reason that these systems (Bluetooth, Wi-Fi and unifying) use 2.4GHz is because it’s unregulated. So if one Bluetooth device interferes with another, but not other bands, then it won’t be breaking any laws. But it might be breaking a contract about the use of the Bluetooth or Wi-Fi logos.

Important distinction: the 2.4 GHz spectrum is _unlicensed_, not unregulated. E.g. ETSI EN 300 328 regulates bandwidth usage, duty cycle, output power and so on in the EU. Products carrying the CE mark should adhere to these standards.

> Products carrying the CE mark should adhere to these standards.

And what evidence is there that Logitech MX products don't?

Re: Logitech MX Products are incompatible with AirPods

#245

Earlier quoted context omitted.

Why did that stop happening? I remember back in the early 2000s you might even come across a live concert where an incoming text message got caught in the PA and broadcast to the entire audience.

Because we moved from GSM and its original set of frequencies to 3G and (usually) a new set of frequency bands. The noise was caused by a beat frequency between the ring channel and the call/data channel. Changing either the coding scheme (so you don't get anything like a tone as the beat) or the channel separation (so the beat isn't in audio range) causes it to go away.

Nah, the frequencies are stil around there, they're all too high to hear, but GSM used TDM - time division multiplex.

To simplify, up to 7 users (+1 timeslot for signalling) share the same channel/frequency, but each of them is allowed to transmit only 1/8 of the time (even less, due to guard intervals). This basically means, that your phone transmitted for a bit over 0.5 milliseconds (577us), then waited quietly for 7 more intervals like that for other devices to transmit, then your phone transmitted again, and the affected speakers "buzzed" because of these 577ms bursts of power every 4.616 milliseconds (this causes a buzz in the frequency range we can actually hear).

Re: Logitech MX Products are incompatible with AirPods

#246

Earlier quoted context omitted.

Why did that stop happening? I remember back in the early 2000s you might even come across a live concert where an incoming text message got caught in the PA and broadcast to the entire audience.

Wow. I've just for the first time ever realised that you might be able to derive the content of the SMS from the specific pattern of interference you would hear on speakers. Like, it seems plausible that is the case. Is that what you mean here by broadcast - or just the fact there was a message was broadcast?

Not really, speakers just reacted to the bursts of power, because the transmission frequency is way too high for us to hear.

GSM uses time division multiplex, which means it shares the 8-timeslot channel with 6 more devices (7 devices + 1 signalling), meaning your phone transmits for 577us, then waits quietly for all the 7 timeslots that other devices use (so, for 4.039 milliseconds - 7x577us), and again transmits for 577us, and again waits. Bursts of power every ~4.6milliseconds make a noise that we can actually hear at a bit over 200Hz.

Re: Logitech MX Products are incompatible with AirPods

#247

Earlier quoted context omitted.

I've also found that if I used the Logitech "unifying" adapter, I _still_ had significant 2.4Ghz spectrum interference -- the Logitech adapter was causing my bluetooth headset (also in the 2.4Ghz spectrum) to have significant connectivity issues, and was also causing interference with some game controllers that operated on the 2.4Ghz spectrum in the same room. The Logitech devices connected to that dongle (an MX Mast…

I don't understand how Logitech mice are so popular given how frequently they fail due to switch problems. Everyone I know, from casual users to gamers, has had problems with logitech mouse button failures. Sometimes within months of purchase, even on their high end gaming mice that cost well north of $100, the buttons will stop working or start double-clicking.

Interesting. This isn't to argue against that experience, but I still have and regularly use a wireless Logitech mouse that's at least around a decade old. I had my previous one for years in daily use as well, although I can't remember how it failed or why I replaced it.

I wonder if they've changed something about the buttons.

Re: Logitech MX Products are incompatible with AirPods

#248
sounds more like this is on Apple which systematically designs their bluetooth devices such that they exhibit uncooperative interfacing. f.x. my airpods won't connect to my Linux notebook (Sony, Bose - all work). my iPhone won't connect to my TomTom navi (various Android smartphones - no problem). same for hotspot settings which refuse connection from Android. Apple is a digital bully.

furthermore I am using a Logitech MX Anywhere 3 mouse via bluetooth and at the same time use either Bose QC35 or EarBuds also via bluetooth. no problem. so that's that ...

Re: Logitech MX Products are incompatible with AirPods

#249
post #222

Earlier quoted context omitted.

The whole reason that these systems (Bluetooth, Wi-Fi and unifying) use 2.4GHz is because it’s unregulated. So if one Bluetooth device interferes with another, but not other bands, then it won’t be breaking any laws. But it might be breaking a contract about the use of the Bluetooth or Wi-Fi logos.

The whole point of 2.4GHz band is to be a "dump" band due to interference from microwave ovens, and happens to be a global band because of microwave ovens on airliners.

I'd love to hear the history of it, because my understanding was that the 2.4 GHz band would be useless for long-distance communication even without microwave ovens, due to atmospheric attenuation. That is, 2.4 GHz is useful for microwave ovens and useless for long-distance radio for the same reason, because they are easily absorbed by water.

Re: Logitech MX Products are incompatible with AirPods

#250

To summarize: If you use a Logitech bluetooth device, it creates enough interference that high-bandwidth products like the Airpods will not function correctly. If you switch the Logitech device to use their "unifying" adapter, which doesn't use bluetooth but a different proprietary wireless protocol, the problem goes away. Logitech acknowledged the problem about six months ago but thus far have deflected any further…

Well, my Bose QC35 and EarBuds both work via bluetooth while also using a Logitech MX Anywhere 3 also via bluetooth. So, I'd conclude that Apple is the culprit here.
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