Can't connect to any device under Ubuntu 18.04

I’ve just gotten the UBS-BT4LE in the mail today and was anxious to finally get everything set up with my Ubuntu PC. But sadly none of the devices I’ve tried so far seem to work properly.
The system seems to recognise the adapter alright. It shows up under lsusb, I can turn bluetooth on and off as one would expect, and even all the nearby bluetooth devices are being “seen” by the PC now.
But when I try to actually connect to any of them, some strange things happen.
My headphones are not recognised as such, and trying to connect or pair to them just fails. I’ve tried this with blueman as well to no avail. I think for a brief time blueman DID manage to connect to them, but without recognising them as audio devices. I can’t replicate this though.
My Nintendo Switch Pro Controller can be paired, but after trying to run the setup wizard, I get “Device added successfuly [sic], but failed to connect”. Steam also doesn’t recognise it.

My old Laptop (also running Ubuntu 18.04) IS now being recognised and can be connected to, but that took some tries. At the moment I’m transferring a file from that Laptop at around 65 kB/s.

I did buy this device almost exclusively to use with bluetooth headphones and game controllers, so I would really like to fix these issues.

Hi, thanks for your post! I’d like to help.


Bluetooth Profiles in Linux

Bluetooth on Linux is handled primarily through a software project called BlueZ. BlueZ handles much of the software operations associated with interpreting Bluetooth profiles.

Bluetooth profiles are features of Bluetooth such as audio playback (Advanced Audio Distribution Profile [A2DP] and Headset Profile/Hands-Free Profile [HSP/HFP]), input devices (Human Interface Device Profile [HID]) such as mice, keyboards, and game controllers, as well as various other features like exchanging contact information, sending files, etc.

Another software project relating to audio specifically is Pulseaudio.

Nintendo Switch Pro Controller

Game controllers tend to function in one of three ways. A less common implementation is emulating mouse and keyboard functions, an old standard called DirectInput, and a modern implementation called XInput.

The Nintendo Switch Pro Controller functions on DirectInput, which is typically not compatible with most modern games out-of-the-box.


With regards to game controllers, Steam has additional software handlers that help to resolve compatibility issues with a variety of game controllers, such as the non-standard Bluetooth implementation of the DualShock 4, and the use of the DirectInput API used by the Nintendo Switch Pro Controller.

Fixing Issues in Linux

Most issues with Bluetooth in Linux are resolved by updating BlueZ and some other Bluetooth-related dependencies in the OS.

We have a guide on how to do this on this page. Just click the button that says ‘Click to Show Linux Information’ and follow the instructions revealed there.

At the very least, going through these steps should help resolve the issues with getting headphones working.

Fixing Issues With the Nintendo Switch Pro Controller

In most cases, updating BlueZ and the components via the method mentioned above will help get things working. However, Steam is third-party software that can have its own issues that are a bit out of our purview to troubleshoot. Some information on issues with Steam and the Switch Pro Controller can be found here.

If you continue to have issues specifically with the controller, I would recommend contacting Valve for additional support regarding issues with this functionality.


Hopefully this helps give an understanding of some of the underlying issues and a path to solving the problem. If you continue to have issues with your headphones working well with the Plugable Bluetooth Adapter in Linux, please contact us via email at, we’re happy to help!

I followed the instruction on the page you linked, and it doesn’t seem to have changed anything.
My headphones still won’t connect either way.
When I try to connect the controller with the standard bluetooth settings app (I’m guessing that’s bluez?), it is shown as connected for a fraction of a second before it switches back to disconnected.
Under blueman, I can “pair” and “trust” it, but at the end of the setup, I get “Device added successfuly, but failed to connect.” and “Connection Failed: blueman.bluez.errors.DBusFailedError: Input/output error”.

I understand that functionality with Steam is a separate matter to possibly take up with Valve, currently I just want to connect the devices to my PC.

I will send a link to this discussion thread to the mail address you provided.

Thank you already for the prompt and friendly service.

This topic was automatically closed 20 days after the last reply. New replies are no longer allowed.

After working with the thread starter on this issue via our support system, it was determined that the headphones did work after performing updates to various software components.

It was also determined that the Switch Pro Controller was pairing, but that Steam was not correctly accepting inputs from the controller and that further actions were needed such as those described here.