If there’s one feature of macOS which has caused more trouble over the last years it’s Bluetooth. With each new version and its updates, I hope in vain that Bluetooth will work seamlessly, but sooner or later those annoying glitches return: the keyboard that periodically doubles letters or skips one, and those sudden disconnects leaving your mouse or trackpad useless for a few seconds before spontaneously reconnecting. For some, Bluetooth problems are more than minor annoyances and get in their way repeatedly. This article looks at what you can, or rather can’t, do to diagnose them.
The first thing that’s striking about Bluetooth is how it has grown, to encompass all your input devices, audio with the AirPods family, and plays a key role in essential features like AirDrop and Handoff tools. Despite that growth, macOS now has essentially no tools to perform basic checks such as signal strength. Those used to be accessible through the Bluetooth item in the menu bar, but have been missing from there for a while, and even System Information (which gives spot values for Wi-Fi signal strength) merely lists devices.
There’s also nothing like Wireless Diagnostics for Bluetooth. Apple used to provide developers with an excellent utility delivered in the additional tools for Xcode, Bluetooth Explorer, but that hasn’t been updated since 2016 and is now fragile and largely dysfunctional, and of no value in Monterey. Most of the Bluetooth utilities available from the App Store don’t work with Apple Magic peripherals, and don’t give signal strength.
The only tool which could provide good information is iStumbler, which would have cost you around $/€/£10 from the App Store. However, this is currently incompatible with Monterey and has been removed from sale for the moment.
At present, as far as I can see, there is no utility which will help you diagnose Bluetooth problems. Really, none at all.
Unfortunately, Bluetooth operates in the same 2.4 GHz frequency band as many Wi-Fi systems. It’s also particularly prone to interference from unintentional emissions from USB-C connections. As you can’t now look for drop-outs in signal resulting from such interference, or caused by physical obstructions to the propagation path between your Mac and the Bluetooth peripheral, all you can do is try to eliminate unseen causes.
Power down and disconnect all non-essential USB-C peripherals. Reconfigure all Wi-Fi base stations so that any 2.4 GHz service is silenced. Ensure that all your Bluetooth peripherals are in clear line-of-sight with the aerial inside your Mac; internal Bluetooth aerials (antennae) are normally placed in the top of iMacs, and inside the main case of Mac minis and notebooks. The two should also be well within 9 m (30 feet) of one another.
If your Bluetooth problems then improve, or go away altogether, you can buy a better-shielded cable for USB-C connections, and ensure that both ends can communicate easily.
If your Mac is still troubled by frequent disconnect-reconnect events, you’ll need to inspect one in your Mac’s Unified log in your quest for a cause. Unless those events are happening very frequently, the only sensible way to do this is using my own free log browser Ulbow.
Hopefully, iStumbler will soon return to the App Store, and work fully with Monterey. And maybe Apple will realise that, without a Bluetooth utility, Mac users can’t diagnose its problems.