Don’t: Hook too many things up to the same device

The maximum number of Bluetooth connections an up-to-date (as of this article, some time in November of 2021) device can handle is 7. However, trying to run 7 peripherals off of the same device at the same time can affect Bluetooth quality indirectly, by eating up all of the device’s processing power and slowing down data transfer. Jumps and stutters in Bluetooth sound or video quality might be purely the device’s fault, and would show themselves even on a physical connection like HDMI. If you’ve got both Youtube and Spotify open on your phone so you can play movies and songs at the same time (at 720p, of course), a mouse and a screen hooked up to said phone alongside a speaker and some headphones… unless you’ve got the beefiest iPhone or Android on the market, Bluetooth data transfer may suffer as a result. Just because it can stay connected to 7 devices doesn’t mean it can use all of them well, at the same time.

That said, this also means your phone and/or computer might be more capable than you think! And if you have enough processing power to run the apps you need the Bluetooth devices for all at the same time, the world is an oyster.

Don’t: leave Bluetooth on all the time

Bluetooth is still a data connection. If something is able to successfully mimic a device your phone or computer is already familiar with, and the device isn’t already connected, it may be possible to get into your device. Once you turn off and disconnect your wireless headphones, you should turn off the Bluetooth seeking option on your phone lest someone successfully mimic your headphones’ Bluetooth connection info and get in. It might sound silly, and you might have been told that’s no longer possible – but versions of this hack appear with every new version of Bluetooth. In fact, a team of white-hat hackers proved it could still be done with moderate difficulty as of May 2021. Use and enjoy your Bluetooth peripherals when they’re connected, of course, but turn it off if it’s not actively being used!  

Besides, leaving it on wastes battery. Your device will eat battery any time it’s told to look for a connection it can’t find – switching to airplane mode when you don’t have service, and switching off location services when GPS can’t find you will conserve the battery too. It tells the phone to stop looking.

Do: Watch for Interference

Just like Wifi, too many devices too close together can interfere with quality. I’ll compare it to radio station frequencies: if two stations were to play on the same frequency (or even as close together as 98.5 and 98.6) you’d get an unintelligible mix of both. The same can happen with WiFi and Bluetooth, which both rely on waves to carry data.

Those waves need to be different frequencies, or else! This is why sometimes, turning off excess 2.4 GHz access points within a network can actually improve performance, because even though you have to access one that’s further away than the old one, nothing is interfering with the wireless connection as it travels across the office. Luckily, because Bluetooth is weaker than both WiFi and radio, getting to that point is really tough. Not impossible, but tough.

Do: Keep the Device Within 30 feet

Bluetooth has limits. Unlike standard WiFi, which can broadcast 150 feet indoors and 300 feet outdoors on the 2.4 GHz channel, Bluetooth devices can begin to lose connection at 30 feet – less if there’s stuff in the way. If you’re playing music on a speaker, don’t get too far away from it!

While Bluetooth does ‘class’ devices, most of the devices you’ll encounter are going to be class 2, that 10-meter-range class, with a broadcast power strength of 2.5 mW. Class 1 devices can reach up to 100 meters – with a broadcast strength of 100 mW. Most consumers don’t need that much range or have that much power in a handheld device like a phone or computer.

Do: Keep your device charged

Phones are carefully calibrated to provide the same experience at any battery level, meaning you don’t get strange behavior at 10%. That’s because it’s not really 10% – it’s 10% with the caveat that all 10 of those percentage points will be exactly the same until the phone is too drained to continue, at which point it shuts down. On the other hand, Bluetooth devices often don’t feel pressure to create a consistent experience for those last few drops of power, meaning you might get spotty audio or inconsistent mouse movements while the device runs itself out of power.

If you notice your device doing weird things, it might not be interference or a broken device – it might just be the battery.

Don’t: Percussive Maintenance

Don’t hit your device. Just don’t. Bending or dislodging the Bluetooth transmitter chip is going to cause you many more problems than hitting it may potentially solve. Restarting the device is much less likely to have negative side effects (you can damage your screen and hard drive if you hit them too hard). If it works, good for you – just know that it may not always work.

 As far as accidentally concussing your device goes, the odds of it living vary – many Bluetooth mice expect to be dropped or knocked off a desk a few times in their lives, and the manufacturer plans accordingly. Chips also vary in size quite a bit, and this affects how they handle landing, meaning items that need larger chips are less likely to behave the way they used to after being dropped.

Headphones may be more or less vulnerable depending on size and composition, and the same goes for speakers. Ultimately, breaking an internal connection in a little computer will depend on how well the connection was made in the first place, so cheaper devices (and occasionally “whale” items like Dr.Dre speakers) with less solder and less QA will suffer before ones with better connections will. Everything must meet Bluetooth standards to officially call themselves Bluetooth compatible… that only applies to the chip itself. Not everything is assembled to survive reasonable traumas like being dropped or folded wrong.

Do: Name Your Connections

This can prevent someone from sneaking in an unauthorized connection. It’s also a massive QOL improvement. Naming your connections before you have to find them in the sea of available Bluetooth connections elsewhere will save you some time trial-and-erroring at the airport or in the café.

Do: Make Sure it Actually Says Bluetooth on the Package

Bluetooth products, in order to legally use Bluetooth in their advertising and call themselves compatible, must go through the Bluetooth Qualification Process. Unless your product comes from somewhere where trademark isn’t respected and imports don’t get inspected, it should be able to connect to other Bluetooth items without issue and meet all of the minimum standards that Bluetooth lays out for its products. Some are better than others, yes – but there is a minimum level of functionality that comes with the brand name Bluetooth. Anything else is just wireless data transfer!

Sources:

https://www.sony.com/electronics/support/articles/00097458

https://www.bluetooth.com/develop-with-bluetooth/qualification-listing/

https://www.itpro.com/security/359664/new-bluetooth-vulnerability-enables-hackers-to-mimic-genuine-devices