Depois que os fones de ouvido são conectados, não é possível realmente mudar para A2DP. O som é muito pobre. 
. fez algumas alterações e o a2dp funciona somente após reiniciar o bluetooth, mas não funciona após uma reinicialização
seguiu as instruções de
https://sandalov.org/blog/2146/ e https://askubuntu.com/questions/319871/bluetooth-speaker-preferred-mode-high-fidelity-playback-a2dp-is-not-getting
mudou dois arquivos
primeiro arquivo /etc/bluetooth/main.conf adicionado as últimas três linhas ao original
[General]
# Default adapter name
# Defaults to 'BlueZ X.YZ'
#Name = BlueZ
# Default device class. Only the major and minor device class bits are
# considered. Defaults to '0x000000'.
#Class = 0x000100
# How long to stay in discoverable mode before going back to non-discoverable
# The value is in seconds. Default is 180, i.e. 3 minutes.
# 0 = disable timer, i.e. stay discoverable forever
#DiscoverableTimeout = 0
# How long to stay in pairable mode before going back to non-discoverable
# The value is in seconds. Default is 0.
# 0 = disable timer, i.e. stay pairable forever
#PairableTimeout = 0
# Automatic connection for bonded devices driven by platform/user events.
# If a platform plugin uses this mechanism, automatic connections will be
# enabled during the interval defined below. Initially, this feature
# intends to be used to establish connections to ATT channels. Default is 60.
#AutoConnectTimeout = 60
# Use vendor id source (assigner), vendor, product and version information for
# DID profile support. The values are separated by ":" and assigner, VID, PID
# and version.
# Possible vendor id source values: bluetooth, usb (defaults to usb)
#DeviceID = bluetooth:1234:5678:abcd
# Do reverse service discovery for previously unknown devices that connect to
# us. This option is really only needed for qualification since the BITE tester
# doesn't like us doing reverse SDP for some test cases (though there could in
# theory be other useful purposes for this too). Defaults to 'true'.
#ReverseServiceDiscovery = true
# Enable name resolving after inquiry. Set it to 'false' if you don't need
# remote devices name and want shorter discovery cycle. Defaults to 'true'.
#NameResolving = true
# Enable runtime persistency of debug link keys. Default is false which
# makes debug link keys valid only for the duration of the connection
# that they were created for.
#DebugKeys = false
# Restricts all controllers to the specified transport. Default value
# is "dual", i.e. both BR/EDR and LE enabled (when supported by the HW).
# Possible values: "dual", "bredr", "le"
#ControllerMode = dual
# Enables Multi Profile Specification support. This allows to specify if
# system supports only Multiple Profiles Single Device (MPSD) configuration
# or both Multiple Profiles Single Device (MPSD) and Multiple Profiles Multiple
# Devices (MPMD) configurations.
# Possible values: "off", "single", "multiple"
#MultiProfile = off
# Permanently enables the Fast Connectable setting for adapters that
# support it. When enabled other devices can connect faster to us,
# however the tradeoff is increased power consumptions. This feature
# will fully work only on kernel version 4.1 and newer. Defaults to
# 'false'.
#FastConnectable = false
# Default privacy setting.
# Enables use of private address.
# Possible values: "off", "device", "network"
# "network" option not supported currently
# Defaults to "off"
# Privacy = off
[Policy]
#
# The ReconnectUUIDs defines the set of remote services that should try
# to be reconnected to in case of a link loss (link supervision
# timeout). The policy plugin should contain a sane set of values by
# default, but this list can be overridden here. By setting the list to
# empty the reconnection feature gets disabled.
#ReconnectUUIDs=00001112-0000-1000-8000-00805f9b34fb,0000111f-0000-1000-8000-00805f9b34fb,0000110a-0000-1000-8000-00805f9b34fb
# ReconnectAttempts define the number of attempts to reconnect after a link
# lost. Setting the value to 0 disables reconnecting feature.
#ReconnectAttempts=7
# ReconnectIntervals define the set of intervals in seconds to use in between
# attempts.
# If the number of attempts defined in ReconnectAttempts is bigger than the
# set of intervals the last interval is repeated until the last attempt.
#ReconnectIntervals=1,2,4,8,16,32,64
# AutoEnable defines option to enable all controllers when they are found.
# This includes adapters present on start as well as adapters that are plugged
# in later on. Defaults to 'false'.
AutoEnable=true
AutoConnect=true
Disable=Headset
segundo arquivo sendo /etc/pulse/
#!/usr/bin/pulseaudio -nF
#
# This file is part of PulseAudio.
#
# PulseAudio is free software; you can redistribute it and/or modify it
# under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# PulseAudio is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with PulseAudio; if not, see <http://www.gnu.org/licenses/>.
# This startup script is used only if PulseAudio is started per-user
# (i.e. not in system mode)
.fail
### Automatically restore the volume of streams and devices
load-module module-device-restore
load-module module-stream-restore
load-module module-card-restore
### Automatically augment property information from .desktop files
### stored in /usr/share/application
load-module module-augment-properties
### Should be after module-*-restore but before module-*-detect
load-module module-switch-on-port-available
### Load audio drivers statically
### (it's probably better to not load these drivers manually, but instead
### use module-udev-detect -- see below -- for doing this automatically)
#load-module module-alsa-sink
#load-module module-alsa-source device=hw:1,0
#load-module module-oss device="/dev/dsp" sink_name=output source_name=input
#load-module module-oss-mmap device="/dev/dsp" sink_name=output source_name=input
#load-module module-null-sink
#load-module module-pipe-sink
### Automatically load driver modules depending on the hardware available
.ifexists module-udev-detect.so
load-module module-udev-detect
.else
### Use the static hardware detection module (for systems that lack udev support)
load-module module-detect
.endif
### Automatically connect sink and source if JACK server is present
.ifexists module-jackdbus-detect.so
.nofail
load-module module-jackdbus-detect channels=2
.fail
.endif
### Automatically load driver modules for Bluetooth hardware
.ifexists module-bluetooth-policy.so
load-module module-bluetooth-policy
load-module module-switch-on-connect
.endif
.ifexists module-bluetooth-discover.so
load-module module-bluetooth-discover
.endif
### Load several protocols
.ifexists module-esound-protocol-unix.so
load-module module-esound-protocol-unix
.endif
load-module module-native-protocol-unix
### Network access (may be configured with paprefs, so leave this commented
### here if you plan to use paprefs)
#load-module module-esound-protocol-tcp
#load-module module-native-protocol-tcp
#load-module module-zeroconf-publish
### Load the RTP receiver module (also configured via paprefs, see above)
#load-module module-rtp-recv
### Load the RTP sender module (also configured via paprefs, see above)
#load-module module-null-sink sink_name=rtp format=s16be channels=2 rate=44100 sink_properties="device.description='RTP Multicast Sink'"
#load-module module-rtp-send source=rtp.monitor
### Load additional modules from GConf settings. This can be configured with the paprefs tool.
### Please keep in mind that the modules configured by paprefs might conflict with manually
### loaded modules.
.ifexists module-gconf.so
.nofail
load-module module-gconf
.fail
.endif
### Automatically restore the default sink/source when changed by the user
### during runtime
### NOTE: This should be loaded as early as possible so that subsequent modules
### that look up the default sink/source get the right value
load-module module-default-device-restore
### Automatically move streams to the default sink if the sink they are
### connected to dies, similar for sources
load-module module-rescue-streams
### Make sure we always have a sink around, even if it is a null sink.
load-module module-always-sink
### Honour intended role device property
load-module module-intended-roles
### Automatically suspend sinks/sources that become idle for too long
load-module module-suspend-on-idle
### If autoexit on idle is enabled we want to make sure we only quit
### when no local session needs us anymore.
.ifexists module-console-kit.so
load-module module-console-kit
.endif
.ifexists module-systemd-login.so
load-module module-systemd-login
.endif
### Enable positioned event sounds
load-module module-position-event-sounds
### Cork music/video streams when a phone stream is active
load-module module-role-cork
### Modules to allow autoloading of filters (such as echo cancellation)
### on demand. module-filter-heuristics tries to determine what filters
### make sense, and module-filter-apply does the heavy-lifting of
### loading modules and rerouting streams.
load-module module-filter-heuristics
load-module module-filter-apply
### Make some devices default
#set-default-sink output
#set-default-source input
fazendo meus arquivos
\etc\bluetooth/main.conf