There are a few reasons this could be happening, depending on the operating system used on your PC.
On all versions of Windows, it is important to make sure that the Bluetooth audio device is set as your active audio device for sound output/input. Be sure to check our guide on how to do that.
An issue that can occur on Windows 7, and earlier versions of Windows, is that many modern Bluetooth audio devices incorporate Bluetooth Low Energy (BLE) features from the Bluetooth 4.0 specifications. Unfortunately, Microsoft never implemented BLE support into versions of Windows prior to Windows 8.x.
Without support for BLE, earlier versions of Windows can get confused about how to handle BLE features on devices that have them. This can manifest in a variety of ways such as the PC showing that there are devices it cannot find drivers for, or it may simply appear that a device is connected but won't function. On Windows 7, this can be somewhat addressed by installing the 126.96.36.1990 driver version that we have available for download, rather than the one on the CD that comes with the adapter. This should at least correct issues with newer audio devices that have BLE features.
On Linux, the driver that provides support for Linux to use the Bluetooth radio in the adapter is baked into the kernel. However, there is more to Bluetooth than simply making the radio available.
Linux primarily uses two software libraries to support Bluetooth connections, BlueZ and Pulseaudio. BlueZ is the software layer that understands the various types of data that can be communicated over Bluetooth, such as mouse and keyboard input, controller input, audio, etc. BlueZ itself interfaces with Pulseaudio to provide audio playback and recording.
Unfortunately, the BlueZ and Pulseaudio open-source projects tend to introduce bugs on a regular basis that cause issues with certain devices. Given the added complexity of BlueZ interfacing with Pulseaudio for audio features, there tends to be more issues with Bluetooth audio in particular versus other types of Bluetooth hardware.
It is recommended to check the community forums for your Linux distro to see if there are other users experiencing audio issues on your current version. In addition, here are some other resources you can check for solutions to Bluetooth audio issues in Linux.
In some cases, manually compiling BlueZ and manually updating Pulseaudio components can help. The instructions below were written for Ubuntu 16.x and 18.x, and should be adaptable to other Linux distros by using the appropriate package manager rather than apt.
Note: As of this writing, BlueZ 5.54 is the current version. However, the most recent version that doesn't seem to have significant bugs is 5.52.
- Open a Terminal window, then download and extract BlueZ 5.52
wget http://www.kernel.org/pub/linux/bluetooth/bluez-5.52.tar.xz && tar xf bluez-5.52.tar.xz
- Change to the BlueZ directory
- Install the libraries necessary to successfully build and install BlueZ, as well as additional audio profile support
sudo apt install pulseaudio-module-bluetooth libusb-dev libdbus-1-dev libglib2.0-dev libudev-dev libical-dev libreadline-dev blueman
- Stop Bluetooth services
sudo /etc/init.d/bluetooth stop
- Then—in the BlueZ directory you should still be in—configure, make, and make install
sudo ./configure && sudo make && sudo make install
- Once the install process is complete, restart the PC
- Try pairing and using your Bluetooth audio device again. If you're still having issues using your distro's default Bluetooth pairing interface, try using Bluetooth Manager (blueman) instead.
Of course, beyond these issues with BlueZ and Pulseaudio, it is important to make sure that you've configured your Bluetooth audio device as the default audio device in your distro's sound settings, once pairing has been completed.