Troubleshooting Bluetooth connections in OS X

BluetoothIconXIf you use Bluetooth devices such as speakers and headphones, mice, keyboards, and printers with your Mac, there may be instances where you might run into connectivity issues, resulting in regular pauses or other disconnections between your Mac and the device. These can be frustrating to deal with, so if you are experiencing them then there are several ways you can go about increasing the stability of your bluetooth connections.

Bluetooth uses a high frequency radio to establish connections between devices, and as with any radio signal, especially those used for digital connections, if there is a poor signal to noise ratio for the connection data will be lost and need to be resent, in order for the connection to be maintained. For Bluetooth devices, the signal strength is computed into a Received Signal Strength Indication (RSSI) value, where the following values in this computation are an approximate guide for a good versus bad connection:

RSSI values for specific devices

The RSSI value is here in the system’s Bluetooth menu

0 to -60 –> good
-61 to -70 –> OK
-71 to -90 –> poor
less than -90 –> bad

These values are always being computed by the Bluetooth devices and drivers in your Mac, and there are several ways to look them up, if needed:

  1. The BlueTooth menuYou can activate the Bluetooth menu extra in the Bluetooth system preferences, and then you can hold the Option key while clicking the menu to show additional information about your Bluetooth connection. The RSSI value should be listed in the sub-menu of each device with an active connection (those in bold).

    RSSI values in system preferences

    Holding the Option key will reveal the RSSI value in the Bluetooth system preferences.

  2. The BlueTooth system preferencesThe Bluetooth system preferences also can be used to show the RSSI value for attached devices. Simply hold the Option key when you see the list of devices, and a small bar graph with an RSSI number should appear that shows you the signal strength of the device.

    Bluetooth RSSI graph

    RSSI values above -60 are generally good, in this case where a mouse is moved closer to the Mac.

  3. The RSSI chartIn the Bluetooth system preferences there is a small gear menu, containing an option to “Monitor Connection RSSI” for any of your configured Bluetooth devices. This graph will show you a 10-minute history of your Bluetooth RSSI values, which you can use to determine if a change in RSSI is a temporary issue or one that might be longer lasting.

Potential causes and fixes

Sometimes low RSSI values can be a temporary issue, but if you have regular drop-outs, then there are several things you can do to fix them. First, be sure the batteries on your Bluetooth your devices are properly charged or are otherwise fresh. This may be viewable in either the Bluetooth menu or the Bluetooth system preferences by selecting “Show more info” from the gear menu, and some devices may have an onboard battery status indicator. These options may depend on the device.

Even if the batteries are in good health and charged, inspect your batteries manually (if possible) to see if there are any leaks or corrosion. Also check the connectors to ensure they are not bent away from the battery, and that the battery has a snug fit. Any of these occurrences can result in a disconnection from a small jerk or other sudden movement of your device.

The next step is to locate your Mac’s Bluetooth antenna, which can be done by opening the RSSI chart and then placing a Bluetooth device at a different location around your system. Then check where the RSSI values for this device are highest. If your environment has a lot of electromagnetic noise that interferes with the Bluetooth signal, then this will be your best bet to ensure the signal strength is as far above the noise as you can get it, and hope that helps the connection. Try using your device as close to your antenna as possible, and then see if this shows better performance.

Conversely, you can try to tackle a poor quality connection by removing (or moving away from) potential shields and noise generating devices from the vicinity. These can include other electronics, especially large large metal objects (including pipes and wiring in walls, metal screen doors, or even coatings on windows).

If you are use a MacBook system, then you might find the Bluetooth signal quality lower when you use the system in clamshell mode (lid closed while connected to an external monitor and keyboard), so try opening the system or repositioning it to see if you can eke out a cleaner signal that way.

8 thoughts on “Troubleshooting Bluetooth connections in OS X

  1. Juan

    Is there any way to connect iPhone iOS with mavericks via Bluetooth to, for example, control a Keynote presentation?

    Thanks

    1. knuthf

      Juan, this is an excellent idea and to be blunt, I have seen a remote control for Mac on Android that will do just this – allowing the phone to be used as a remote controller that emulates keystrokes. I wonder if you can use XBMC for the same.

  2. Steve P

    Excellent article, but there’s no mention of BT hearing aid connectivity with an iPhone or iPad. My ReSound Linx aids are BT connected. No real problems, but you should have the iPhone should be close to you when turning on the aids. Also, there are is no “additional information”, such as that shown above, on i devices.

  3. Alan

    Bluetooth preferences in 10.9.3 build 13D65 on late 2013 13″ rMBP has a different appearance than yours. There is no gear menu; there’s panel on right shows currently and previously paired devices, left side of window has huge Bluetooth icon, below shows status as “On”, button to turn Off. Any ideas?

    1. B. Jefferson Le Blanc

      Exactly. The Option key reveals neither the bar graph nor the RSSI value. Nor do I see a gear icon to show other functions. Now the Bluetooth preference pane never ceases scanning; could this be interfering with the other functions?

      On the other hand, holding down the Option key while clicking on the Bluetooth menu bar icon reveals a list of additional utilities, including the Bluetooth Explorer and Diagnostic Utility. However, the Explorer crashes on me whenever I try to do anything with it. In theory these tools could help troubleshoot Bluetooth problems.

  4. didymus

    The old Mac Pros in the form factor prior to this generation are notorious for their bad Bluetooth connectivity. The Bluetooth antenna is located inside the aluminum case.

    1. knuthf

      The RSSI is sort of utter rubbish. Bluetooth is a technology developed in Europe (Ericsson & Nokia) for mobile phones. It uses the 2.4GHz frequency – same as WLAN. BT use “frequency hopping” derived from DECT cordless handset. So the 2.4GHz does not have “channels” but unique RF frequencies. A “magic number” that is exchanged during set-up is used to calculate the next frequency, that will change all the time. The “sender” will listen to the “next” frequency before using it, and skip should it be used, so should a packet not arrive, the next will be used. Connected devices can thus communicate safely, it is possible to listen-in, but very difficult. The frequency hopping allows this to coexist with WLAN – as long as not all channels are taken. It also provides a warranted “Quality of Service” (unlike WLAN) which allows streaming transfer.

      Since this is a standard technology with approved “profiles” – Apple cannot make their own, and the “empire cannot rule” – just adhere.

  5. lordthistle

    I have an aptX enables receiver for streaming music to my stereo amplifier. Every time I ‘move’ my Macbook Pro (2012, no retina) and, occasionally, when I switch apps the RSSI drops and the sound has several glitches. Is this a known problem?

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