Bluetooth is becoming increasingly unreliable on Mac OS X. The steps below will undertake a hardcore reset of Bluetooth hardware and software components. This will remove any devices you have paired and essentially return the Bluetooth system to factory-fresh state.
Consider this a last resort if other Bluetooth trouble-solving steps haven’t worked.
Obviously, if you use a Bluetooth keyboard and/or mouse you’ll need to either use your Mac’s built-in keyboard and trackpad for these steps, or temporarily attach USB devices.
Before undertaking these steps also see this discussion about weak Bluetooth signals competing with Wi-Fi, and how switching to a 5GHz Wi-Fi signal could solve some problems for you.
- For these steps you’ll need the Bluetooth menu icon visible. If it isn’t, open System Preferences, click the Bluetooth icon, and then put a check in the box marked Show Bluetooth In Menu Bar.
- Hold down Shift+Option (Alt on some keyboards) and click the Bluetooth icon on the menu bar.
- On the menu that appears click Debug > Remove All Devices. At this point any existing devices you have paired will stop working.
- Repeat step 2 and this time select Debug > Reset the Bluetooth Module.
- Reboot your Mac. When the Mac restarts, add your Bluetooth devices as if setting up a new Mac.
In addition to the above steps you might also consider undertaking a SMC reset.