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Comment by ahartmetz | Hacker News Reader

The problems with Bluetooth are it doesn't pair, it doesn't unpair, you need to unpair first, you need to use the other protocol that transmits audio, the latency is way too high, it's insecure, the software stack hangs or crashes, you can't know for sure if two devices will work together, BLE is WAY too low level and a step back, the spec is way too big and complicated, ... In 20 years they have not managed to make it good. It seems hopeless with the current institutions managing it. What a heap of hot garbage.

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I agree with you, except about Bluetooth LE. LE (4.0) is a totally different protocol than 'classic' Bluetooth (<= 3), and shares no heritage. Nokia came up with the LE spec and dropped it down on the desk at the Bluetooth SIG and told them this was Bluetooth now ("wibree", [1]). The LE family is just a short couple of years old now, not 20.

For many of the tasks you'd want high bandwidth for, you probably want WiFi (or even point-to-point WiFi established over Bluetooth LE like AirDrop). LE is a huge step forward because it distinguishes between the two major use cases (low bandwidth - low power - promiscuous mode vs. high-bandwidth - paired) and allows for the development of standards which meet each use case without compromise. Part of why Bluetooth was pretty garbage before is that its use cases overlapped so heavily with WiFi, but it wasn't allowed to (or ever going to) replace it. This lead to this weird hybrid high-power, middling bandwidth, paired but you-probably-dont-want-it-to-be spec.

LE 2 (Bluetooth 5) addresses some of your concerns by increasing the bandwidth available for LE devices, without compromising on power efficiency.

[1] https://en.wikipedia.org/wiki/Bluetooth_Low_Energy

How do I tell if a device is Bluetooth LE though? It still pairs in the same list as all the other Bluetooth devices and I don't see anything that identifies it otherwise. So it kinda sucks for LE devices to get the "bad rep" because as far as consumers are concerned, LE devices suck as well, they just don't display those same issues all the time.

LE is a different spec and behaves completely different from traditional Bluetooth. People assume Bluetooth 4+ is LE but it's not. If you're pairing with a device in the traditional Bluetooth sense, it's not LE.

... ok, so how do you know you're using LE?

It's easier to tell when you're not using BLE. :)

The Tesla Model 3 uses traditional Bluetooth for phone calls and streaming but the Phone as a Key functionality is BLE. When you walk up to the car and try to open it and the car says FU then BLE isn't working.

When your Xiaomi Mi Band smartwatch hasn't buzzed all day but you pull your smartphone out of your pocket and have 8 missed calls, 100 messages, and 500 emails then BLE isn't working.

When you're at a Tech Conference and the Conference App uses BLE Beacons to help navigate you indoors and it can't determine your location then BLE isn't working.

Bluetooth LE may be only a few years old, but it already has a split between insecure legacy pairing modes that shouldn't be used and actually-decent pairing modes that only work on newer devices.

Yeah if I recall that was due to issues with security if an attacker observed the initial key exchange in 4.0 and was resolved in 4.2 and 5, right?

If you're streaming audio over Bluetooth (i.e. headphones or speakers), you're not using BLE, you're using classic Bluetooth, and none of this matters. BLE didn't have the bandwidth for audio until 4.2, and still doesn't have an audio standard like classic Bluetooth's headset profile.

Every Bluetooth device I have ever tried has failed to meet my expectations. I have a drawer full of Bluetooth devices that I regret purchasing. I've been fooled too many times already, I simply won't buy a device that relies on Bluetooth any more. For mouse/keyboard I like RF and for audio you can pry my 3.5mm jack from my cold dead hands.

The AirPods are magical. The only time the magic breaks down is when you're in a place where there is a ton of signal interference (e.g. walking around in busy parts of Manhattan). Aside from that, they're about as close to Just Works as anything I've ever used in my life.

Yeah, but they're pretty mediocre headphones in terms of sound quality, and they're built as a single unit making them impossible to recycle.

From what I understand they also don't fit/stay in a lot of people's ears. A lot of in-ear headphones come with different sizes for this reason.

They actually stay better even if wired Apple earbuds do not. There is no wire pulling them out.

I don't quite understand why you're being down-voted here for a very reasonable statement. I suppose that perhaps 'a lot' is a bit hyperbolical, and it is realistically closer to 'a small few'. I had AirPods for a while, but they simply did not fit comfortably in my ears. I bought some Jabra brand wireless headphones, which come with a selection of different sized buds, and I'm very satisfied with them thus far. They don't quite have the "sleek" look that Apple does so well, but the side button functions are excellent and the call quality seems clearer when in noisy areas. I've had a few friends complain about their AirPods just about not fitting, and I always recommend the Jabra's now.

As a headphone buff and snob, I respectfully disagree. I think they sound wonderful, and I own Sennheiser HD1s and HD820s. For as small and portable and convenient and affordable as they are, they are far higher audio quality than I would expect. I use them all of the time.

So it breaks when you need it the most? Gotcha

"Hey let's make everybody use the unregulated band for a basic function so that we make our phones thinner and we can sell more expensive accessories, how about that"

I've found (after many bad buys) a pair of cheap bluetooth headphones that 'just work' with my iphone. The problem is, there is no way for a customer to tell whether a bluetooth device is going to work well or not (or even not at all!)

Bluetooth can be good but there are just too many devices which are 'bluetooth compatible' in theory but have many odd incompatibilities. Perhaps it is the complexity of the spec that causes this to happen to bluetooth, rather than wifi...

I was initially rather skeptical of bluetooth headphones - but after yet another gardening related headphone incident I bought a cheap pair (£30) and they worked perfectly well. They broke (headband snapped) and I upgraded to moderately priced Sony ones (~£100).

I've literally never had any problems connecting any of these to any devices (desktop PC, iPads, iPhones).

Bluetooth also seems to work pretty much perfectly with my car as well.

I'm not doubting you have problems - but interesting to note that for some people Bluetooth does actually seem to work.

Same with me. I’ve had two bluetooth headphones, one pair from sony and one pair from bower & wilkins. Never had problem with them.

I'm surprised when it works.

I still don't know how to unpair on some black boxes. My partner has a speaker, and I think auto-pairing occurs if used previously, so we have a strange ritual of turning off bluetooth on other devices until it seems to correct itself when wanting to use it.

I've always assumed this was a UI issue.

I've had phones that have presented themselves as a pointing device to a computer. Some as modems. Some that have transferred/pushed files okay on some OSs, not others. I have no idea what's going on with Bluetooth most of the time, and it's quite infuriating. On Linux Blueman doesn't give much away. On a Windows PC I have, using Bluetooth kills WIFI, and requires a reboot to fix.

From a mobile perspective if I say try and transfer a file from a phone, it can turn Bluetooth on, fail and then leave it on.

Wireless headphones sound like a great idea though! But again not sure which protocols are being used. Again that's a UI issue, I've a streaming speaker - and have no idea about the stream quality of what I'm listening to. Oh for some simple feedback diagnostics.

We have a couple of those bluetooth speakers (UE Booms) and I've never had a problem with them either!

Mind you - I never 'unpair' a device - I just set the BT device to be in pairing mode (or whatever it is called) and then connect from my phone/tablet and that removes the previous connection. Having to do this on both devices and that the step necessary to initiate pairing is device specific is the only issue I have with BT - but it's a relatively minor one.

Funnily, I had the almost the same experience (started with a cheap pair of headphones, loved them, broke them, went on to a ~100EUR Sony pair). With Android never had any problem with bluetooth devices. Windows almost never.

Linux though is a complete disaster: when I turn the headphones on I _always_ have to manually disconnect them and reconnect. Even so, from time to time they stick to the audio only profile and there is not way to use the embedded microphone unless I disconnect them, turn them off, turn them on and repeat the incantation.

I have a pair of moderately priced Sony BT headphones. Could be a similar model given the price range.

You can't charge and listen at the same time (wtf)

I get no warning when the battery is about to die (combined with the above this really sucks, they shut off in the middle of something)

I dual boot OSX and Windows on my laptop and I have to re-pair the headphones every time I switch OSes. I suspect each OS has a different encryption key, but the headphones can't tell the difference between which OS is running.

They cut out and skip all the time when walking through the City. They are borderline unusable when walking between the train station and my office.

They cut out and skip occasionally when not walking through the City, for no discernable reason.

They have an obnoxious and unnecessary blue LED that blinks periodically when they are turned on. This lights up our whole bedroom at night and annoys the crap out of my wife. I have to keep a piece of black electrical tape over the LED.

These are the best bluetooth headphones I have ever owned, they sound great, and I absolutely hate them.

My favorite regular reason for mine cutting out and skipping is when I turn my head to the right.

These were an inexpensive model, but were nonetheless very well-reviewed on many tech sites, and often recommended as one of the top budget options.

Mine are the MDR-XB650BT - I checked and they were probably cheaper than I thought (probably ~£60).

I use mine when I commute by train into Edinburgh and they really haven't given me any problems - I didn't even know they had a blue LED until I checked there... :-)

Battery life is good enough for my purposes - but I do make a point of keeping them charged up as I live in fear of a commute without an audiobook! They certainly don't cut out for me.

"I dual boot OSX and Windows on my laptop and I have to re-pair the headphones every time I switch OSes. I suspect each OS has a different encryption key, but the headphones can't tell the difference between which OS is running."

Your suspicion is correct.

The real problem is that Apple and Microsoft both have not provided any way to specify the key to connect with, and they both paired independently, creating a different key each time.

One solution would be to find where the link key was stored in one of the OSs and copy it over to the other OS. Then they would both use the same link key and you are good to go until you re-pair for some reason. I don't know if this (still) works, but some instructions are here:

  https://www.insanelymac.com/forum/topic/268837-dual-boot-bluetooth-pairing-solved/

A different solution could be that the Bluetooth adaptor usually has a way to store the link key within the device in NVRAM. The technicality of that is that the adaptor does never ask the OS for the link key, it just connects. I don't know if tools exist in OSX or Windows to do that, however.

I had zero problems while using Apple products: mouse, keyboard and Airpods. Other two non-Apple products: Withings watch and Honda Civic gave me no problems either.

Microsoft makes excellent Bluetooth keyboards and mice. Sennheiser does OK with headphones, with their newest models being markedly better than ones even to years ago. There are also a few, rare, small companies that do a pretty good job: TechNet and AfterShokz come to mind.

All the Bluetooth issues being downplayed in this thread are a far cry from wired headphones that just work.

They're getting better. It's a little reminiscent of Android, actually, which wasn't really solid until KitKat.

For example, I have a microsoft bluetooth mouse that is utterly painless & two AA batteries last for something like a year working full time. Also have a pair of Jabra 65t, pairing is annoying and on rare occasions it hiccups, but 97% of the time they are excellent. I had owned BT mice & headphones previously, and they have never been better than today.

Those aren't problems of Bluetooth, those are problems of device implementations. The BT protocol makes it possible to manage pairings, un-pairings, and re-pairings, in any which way that makes good sense for the user. But a lot of device manufacturers don't spend the time to read even the most basic parts of the spec necessary to manage connections.

For example, a lot of re-pairing issues come about from the device resetting its own device ID. Some rare devices do this on every soft-power-cycle. A good many devices do it on recovering from power-failure (e.g. dead battery). At that point, the device is basically a completely different "device". The best devices keep their device ID in non-volatile memory so they can recover from power failure without resetting their device ID.

Having built a few BT devices as a hobbyist, it's not really that hard to make a good pairing experience. You just have to... think things through and not do the most bare minimum work.

Yes, when it comes to protocols a lot of companies seem to have an attitude of "when it works, don't touch it", and the result is a mediocre experience because they forget to look at the edge cases.

Perhaps BT would be better with certification.

I have many BT devices, from budget to high-end, and they all have problems, from minor to major.

I stress "from minor to major"; in my experience BT does ultimately work, but there are always minor, odd, kinks like (I assume) an Android update preventing my headhphones to establish a "media" connection 50%+ of the time.

Given that also my high-end devices are subject to problems (eg. ~400$ mobile phone with ~400$ headphones), then the specification may be technically correct but practically unusable.

To me, "practically unusable" == "broken".

Having implemented a few devices, honestly, the spec couldn't be more straight forward. It's really a case of hardware engineers being terrible at user experience. Just because a device is expensive doesn't mean the company has put all necessary effort into the BT stack. Look at how many "simple" things Apple, Google, and Facebook screw up on a daily basis.

And you forgot one: it seems impossible to pair (e.g.) two headphones with a single phone. This makes it impossible to listen with a buddy to a single audio source.

And they wonder why there's resistance to phones that are wireless only.

Their wireless audio protocol is bad and they should feel bad.

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