Bluetooth configuration

Bluetooth audio and MIDI devices are managed by the BlueZ and BlueZ-MIDI monitors, respectively.

Both monitors are enabled by default and can be disabled using the monitor.bluez and monitor.bluez-midi features in the configuration file.

As with all device monitors, both of these monitors are implemented as SPA plugins and are part of PipeWire. WirePlumber merely loads the plugins and lets them do their work. These plugins then monitor the BlueZ system-wide D-Bus service and create device and node objects for all the connected Bluetooth audio and MIDI devices.

Logind integration

The BlueZ monitors are integrated with logind to ensure that only one user at a time can use the Bluetooth audio devices. This is because on most Linux desktop systems, the graphical login manager (GDM, SDDM, etc.) is running as a separate user and runs its own instance of PipeWire and WirePlumber. This means that if a user logs in graphically, the Bluetooth audio devices will be automatically grabbed by the PipeWire/WirePlumber instance of the graphical login manager, and the user that logs in will not get access to them.

To overcome this, the BlueZ monitors are integrated with logind and are only allowed to create device and node objects for Bluetooth audio devices if the user is currently on the "active" logind session.

In some cases, however, this behavior is not desired. For example, if you manually switch to a TTY and log in there, you may want to keep the Bluetooth audio devices connected to the now inactive graphical session. Or you may want to have a dedicated user that is always allowed to use the Bluetooth audio devices, regardless of the active logind session, for example for a (possibly headless) music player daemon.

To disable this behavior, you can set the monitor.bluez.seat-monitoring feature to disabled.

Example configuration fragment file:

wireplumber.profiles = {
  main = {
    monitor.bluez.seat-monitoring = disabled
  }
}

Note

If logind is not installed on the system, this functionality is disabled automatically.

Monitor Properties

The BlueZ monitor SPA plugin (api.bluez5.enum.dbus) supports properties that can be used to configure it when it is loaded. These properties can be set in the monitor.bluez.properties section of the WirePlumber configuration file.

Example:

monitor.bluez.properties = {
  bluez5.roles = [ a2dp_sink a2dp_source bap_sink bap_source hsp_hs hsp_ag hfp_hf hfp_ag ]
  bluez5.codecs = [ sbc sbc_xq aac ]
  bluez5.enable-sbc-xq = true
  bluez5.hfphsp-backend = "native"
}

These properties are implemented by the BlueZ SPA plugin, which is part of PipeWire. Their complete reference is the pipewire-props(7) man page, which is also available online at https://docs.pipewire.org/page_man_pipewire-props_7.html - see the "BLUETOOTH PROPERTIES / Monitor properties" section there. The list below is a selection only, covering the properties that are most commonly changed.

bluez5.roles

Enabled roles.

Currently some headsets (e.g. Sony WH-1000XM3) do not work with both hsp_ag and hfp_ag enabled, so by default we enable only HFP.

Supported roles:

  • hsp_hs (HSP Headset)

  • hsp_ag (HSP Audio Gateway),

  • hfp_hf (HFP Hands-Free),

  • hfp_ag (HFP Audio Gateway)

  • a2dp_sink (A2DP Audio Sink)

  • a2dp_source (A2DP Audio Source)

  • bap_sink (LE Audio Basic Audio Profile Sink)

  • bap_source (LE Audio Basic Audio Profile Source)

Default value:

[ a2dp_sink a2dp_source bap_sink bap_source hfp_hf hfp_ag ]

Type:

array of strings

bluez5.codecs

Enabled A2DP codecs.

Supported codecs: sbc, sbc_xq, aac, ldac, aptx, aptx_hd, aptx_ll, aptx_ll_duplex, faststream, faststream_duplex, lc3plus_h3, opus_05, opus_05_51, opus_05_71, opus_05_duplex, opus_05_pro, lc3.

Default value:

all available codecs

Type:

array of strings

bluez5.enable-msbc
bluez5.enable-sbc-xq
bluez5.enable-hw-volume

Enable, respectively, the mSBC codec (wideband speech codec for HFP/HSP), the SBC-XQ codec (high quality SBC codec for A2DP) and hardware volume controls.

None of these work on all headsets, so they are enabled based on the hardware quirks database. By explicitly setting these options you can force them to be enabled or disabled regardless.

Default value:

true

Type:

boolean

bluez5.hfphsp-backend

HFP/HSP backend.

Available values: any, none, hsphfpd, ofono or native.

Default value:

native

Type:

string

bluez5.hfphsp-backend-native-modem

Modem to use for native HFP/HSP backend ModemManager support. When enabled, PipeWire will forward HFP commands to the specified ModemManager device. This corresponds to the 'Device' property of the org.freedesktop.ModemManager1.Modem interface. May also be any to use any available modem device.

Default value:

none

Type:

string

MIDI Monitor Properties

The BlueZ MIDI monitor SPA plugin (api.bluez5.midi.enum) may, in the future, support properties that can be used to configure it when it is loaded. These properties can be set in the monitor.bluez-midi.properties section of the WirePlumber configuration file. At the moment of writing, there are no properties that can be set there.

In addition, the BlueZ MIDI monitor supports a list of MIDI server node names that can be used to create Bluetooth LE MIDI service instances. These server node names can be set in the monitor.bluez-midi.servers section of the WirePlumber configuration file.

Example:

monitor.bluez-midi.servers = [ "bluez_midi.server" ]

Note

Typical BLE MIDI instruments have one service instance, so adding more than one here may confuse some clients.

Rules

When device and node objects are created by the BlueZ monitor, they can be configured using rules. These rules allow matching the existing properties of these objects and updating them with new values. This is the main way of configuring Bluetooth device settings.

These rules can be set in the monitor.bluez.rules section of the WirePlumber configuration file.

Example:

monitor.bluez.rules = [
  {
    matches = [
      {
        ## This matches all bluetooth devices.
        device.name = "~bluez_card.*"
      }
    ]
    actions = {
      update-props = {
        bluez5.auto-connect = [ hfp_hf hsp_hs a2dp_sink hfp_ag hsp_ag a2dp_source ]
        bluez5.hw-volume = [ hfp_hf hsp_hs a2dp_sink hfp_ag hsp_ag a2dp_source ]
        bluez5.a2dp.ldac.quality = "auto"
      }
    }
  }
  {
    matches = [
      {
        ## Matches all sources.
        node.name = "~bluez_input.*"
      }
      {
        ## Matches all sinks.
        node.name = "~bluez_output.*"
      }
    ]
    actions = {
      update-props = {
        bluez5.media-source-role = "input"

        ## Common node & audio adapter properties may also be set here
        node.description       = "My Node"
        priority.session       = 100
        session.suspend-timeout-seconds = 5
      }
    }
  }
]

Where the properties are documented

The names that appear inside update-props are PipeWire object properties. They are not defined by WirePlumber: the bluez5.* ones are implemented by the BlueZ SPA plugin, and the rest are common node properties or properties of the audio adapter that PipeWire attaches to every audio node - the very same priority.*, session.*, resample.* and channelmix.* properties that apply to ALSA nodes and to application streams. All of them are documented in pipewire-props(7).

The sections below are a selection only, covering the properties that are most commonly changed on Bluetooth devices. For anything that is not listed here, refer to that man page.

Device properties

bluez5.auto-connect

Auto-connect device profiles on start up or when only partial profiles have connected. Disabled by default if the property is not specified.

Supported values are: hfp_hf, hsp_hs, a2dp_sink, hfp_ag, hsp_ag and a2dp_source.

Default value:

[]

Type:

array of strings

bluez5.hw-volume

Enable hardware volume controls on these profiles.

Supported values are: hfp_hf, hsp_hs, a2dp_sink, hfp_ag, hsp_ag and a2dp_source.

Default value:

[ hfp_ag hsp_ag a2dp_source ]

Type:

array of strings

bluez5.a2dp.ldac.quality

LDAC encoding quality.

Available values: auto (Adaptive Bitrate, default), hq (High Quality, 990/909kbps), sq (Standard Quality, 660/606kbps) and mq (Mobile use Quality, 330/303kbps).

Default value:

auto

Type:

string

Note

The initially activated profile of a Bluetooth device cannot be set with a property: WirePlumber forces it to "off" on creation and then applies its own profile policy. See the bluetooth.profile-preference setting in Well-known settings and the profile priority rules in Profile priorities.

Node properties

bluez5.media-source-role

Media source role, input or playback. This controls how a media source device, such as a smartphone, is used by the system. Defaults to playback, playing the incoming stream out to speakers. Set to input to use the smartphone as an input for apps (like a microphone).

Default value:

playback

Type:

string

MIDI Rules

Similarly to the above rules, the BlueZ MIDI monitor also supports rules that can be used to configure MIDI nodes when they are created.

These rules can be set in the monitor.bluez-midi.rules section of the WirePlumber configuration file.

Example:

monitor.bluez-midi.rules = [
  {
    matches = [
      {
        node.name = "~bluez_midi.*"
      }
    ]
    actions = {
      update-props = {
        node.nick = "My Node"
        priority.driver = 100
        priority.session = 100
        node.pause-on-idle = false
        session.suspend-timeout-seconds = 5
        node.latency-offset-msec = 0
      }
    }
  }
]

Note

It is possible to also match MIDI server nodes by testing the node.name property against the server node names that were set in the monitor.bluez-midi.servers section of the WirePlumber configuration file.

MIDI-specific properties

node.latency-offset-msec

Latency adjustment to apply on the node. Larger values add a constant latency, but reduces timing jitter caused by Bluetooth transport.

Default value:

0

Type:

integer (milliseconds)

The common node properties that may also be set here (node.description, priority.*, session.suspend-timeout-seconds, ...) are documented in pipewire-props(7).