bluez: fones de ouvido bluetooth não podem reconectar após desconectar

Posso emparelhar meu fone de ouvido bluetooth com meu laptop uma vez. Mas quando eu desconecto meu fone de ouvido, não consigo reconectá-lo novamente. A única maneira de funcionar é reiniciar o daemon bluetooth:

service bluetooth restart

Quando faço isso, vejo o seguinte no meu log:

bluetoothd:  Terminating
bluetoothd:  Stopping hci0 event socket
bluetoothd:  Stopping SDP server
bluetoothd:  Exit
bluetoothd:  Bluetooth daemon 4.99
bluetoothd:  Starting SDP server
bluetoothd:  Excluding (conf) network
bluetoothd:  Excluding (conf) gatt_example
bluetoothd:  Excluding (conf) time
bluetoothd:  Excluding (conf) alert
bluetoothd:  Failed to open RFKILL control device
bluetoothd:  Listening for HCI events on hci0
bluetoothd:  HCI dev 0 up
bluetoothd:  Proximity GATT Reporter Driver: Operation not permitted (1)
bluetoothd:  Could not get the contents of DMI chassis type
bluetoothd:  Unable to load keys to adapter_ops: Function not implemented (38)
bluetoothd:  Adapter /org/bluez/8237/hci0 has been enabled

então posso conectar meus fones de ouvido com sucesso:

bluetoothd:  Can't open input device: No such file or directory (2)
bluetoothd:  AVRCP: failed to init uinput for 44:66:a7:81:3C:84
bluetoothd:  Badly formated or unrecognized command: AT+XEVENT=Bose SoundLink,158
bluetoothd:  Badly formated or unrecognized command: AT+BIA=0,0,0,1,1,1,0

Mas quando eu os desconecto e tento conectar novamente, ele não funciona e não vejo nada nos logs.

Por que não consigo reconectar meus fones de ouvido depois de desconectar? Por que preciso reiniciar o daemon bluetooth? Como posso consertar isso ?

Estou usando bluez 4.99no Debian.

Estou usando o kernel personalizado 4.4.

Estou usando o alsa (sem pulseaudio).

É buggy com certas marcas de fones de ouvido. Eu sofro os mesmos problemas e esse script python para reconectar meu fone de ouvido bluetooth funciona para mim.

Certifique-se de ter pelo menos o python 3.5 instalado. As instruções sobre como usar o script são auto-explicativas no cabeçalho:

https://gist.github.com/pylover/d68be364adac5f946887b85e6ed6e7ae

Editar: incluí o código mais recente deste script nesta resposta como uma solicitação, mas eu recomendo obter a iteração mais recente no link fornecido, pois o autor está sempre atualizando o script.

#! /usr/bin/env python3.5
"""
Fixing bluetooth stereo headphone/headset problem in ubuntu 16.04 and also debian jessie, with bluez5.
Workaround for bug: https://bugs.launchpad.net/ubuntu/+source/indicator-sound/+bug/1577197
Run it with python3.5 or higher after pairing/connecting the bluetooth stereo headphone.
This will be only fixes the bluez5 problem mentioned above .
Licence: Freeware
See ``python3.5 a2dp.py -h``.
Shorthands:
    $ alias speakers="a2dp.py 10:08:C1:44:AE:BC"
    $ alias headphones="a2dp.py 00:22:37:3D:DA:50"
    $ alias headset="a2dp.py 00:22:37:F8:A0:77 -p hsp"
    $ speakers
Check here for the latest updates: https://gist.github.com/pylover/d68be364adac5f946887b85e6ed6e7ae
Thanks to:
 * https://github.com/DominicWatson, for adding the ``-p/--profile`` argument.
 * https://github.com/IzzySoft, for mentioning wait before connecting again.
 * https://github.com/AmploDev, for v0.4.0
 * https://github.com/Mihara, for autodetect & autorun service
 * https://github.com/dabrovnijk, for systemd service
Change Log
----------
- 0.5.0
  * Autodetect & autorun service
- 0.4.1
  * Sorting device list
- 0.4.0
  * Adding ignore_fail argument by @AmploDev.
  * Sending all available streams into selected sink, after successfull connection by @AmploDev.
- 0.3.3
  * Updating default sink before turning to ``off`` profile.
- 0.3.2
  * Waiting a bit: ``-w/--wait`` before connecting again.
- 0.3.0
  * Adding -p / --profile option for using the same script to switch between headset and A2DP audio profiles
- 0.2.5
  * Mentioning [mac] argument.
- 0.2.4
  * Removing duplicated devices in select device list.
- 0.2.3
  * Matching ANSI escape characters. Tested on 16.10 & 16.04
- 0.2.2
  * Some sort of code enhancements.
- 0.2.0
  * Adding `-V/--version`, `-w/--wait` and `-t/--tries` CLI arguments.
- 0.1.1
  * Supporting the `[NEW]` prefix for devices & controllers as advised by @wdullaer
  * Drying the code.
"""

import sys
import re
import asyncio
import subprocess as sb
import argparse


__version__ = '0.4.0'


HEX_DIGIT_PATTERN = '[0-9A-F]'
HEX_BYTE_PATTERN = '%s{2}' % HEX_DIGIT_PATTERN
MAC_ADDRESS_PATTERN = ':'.join((HEX_BYTE_PATTERN, ) * 6)
DEVICE_PATTERN = re.compile('^(?:.*\s)?Device\s(?P<mac>%s)\s(?P<name>.*)' % MAC_ADDRESS_PATTERN)
CONTROLLER_PATTERN = re.compile('^(?:.*\s)?Controller\s(?P<mac>%s)\s(?P<name>.*)' % MAC_ADDRESS_PATTERN)
WAIT_TIME = .75
TRIES = 4
PROFILE = 'a2dp'


_profiles = {
    'a2dp': 'a2dp_sink',
    'hsp': 'headset_head_unit',
    'off': 'off'
}

# CLI Arguments
parser = argparse.ArgumentParser(prog=sys.argv[0])
parser.add_argument('-e', '--echo', action='store_true', default=False,
                    help='If given, the subprocess stdout will be also printed on stdout.')
parser.add_argument('-w', '--wait', default=WAIT_TIME, type=float,
                    help='The seconds to wait for subprocess output, default is: %s' % WAIT_TIME)
parser.add_argument('-t', '--tries', default=TRIES, type=int,
                    help='The number of tries if subprocess is failed. default is: %s' % TRIES)
parser.add_argument('-p', '--profile', default=PROFILE,
                    help='The profile to switch to. available options are: hsp, a2dp. default is: %s' % PROFILE)
parser.add_argument('-V', '--version', action='store_true', help='Show the version.')
parser.add_argument('mac', nargs='?', default=None)


# Exceptions
class SubprocessError(Exception):
    pass


class RetryExceededError(Exception):
    pass


class BluetoothctlProtocol(asyncio.SubprocessProtocol):
    def __init__(self, exit_future, echo=True):
        self.exit_future = exit_future
        self.transport = None
        self.output = None
        self.echo = echo

    def listen_output(self):
        self.output = ''

    def not_listen_output(self):
        self.output = None

    def pipe_data_received(self, fd, raw):
        d = raw.decode()
        if self.echo:
            print(d, end='')

        if self.output is not None:
            self.output += d

    def process_exited(self):
        self.exit_future.set_result(True)

    def connection_made(self, transport):
        self.transport = transport
        print('Connection MADE')

    async def send_command(self, c):
        stdin_transport = self.transport.get_pipe_transport(0)
        # noinspection PyProtectedMember
        stdin_transport._pipe.write(('%s\n' % c).encode())

    async def search_in_output(self, expression, fail_expression=None):
        if self.output is None:
            return None

        for l in self.output.splitlines():
            if fail_expression and re.search(fail_expression, l, re.IGNORECASE):
                raise SubprocessError('Expression "%s" failed with fail pattern: "%s"' % (l, fail_expression))

            if re.search(expression, l, re.IGNORECASE):
                return True

    async def send_and_wait(self, cmd, wait_expression, fail_expression='fail'):
        try:
            self.listen_output()
            await self.send_command(cmd)
            while not await self.search_in_output(wait_expression.lower(), fail_expression=fail_expression):
                await wait()
        finally:
            self.not_listen_output()

    async def disconnect(self, mac):
        print('Disconnecting the device.')
        await self.send_and_wait('disconnect %s' % ':'.join(mac), 'Successful disconnected')

    async def connect(self, mac):
        print('Connecting again.')
        await self.send_and_wait('connect %s' % ':'.join(mac), 'Connection successful')

    async def trust(self, mac):
        await self.send_and_wait('trust %s' % ':'.join(mac), 'trust succeeded')

    async def quit(self):
        await self.send_command('quit')

    async def get_list(self, command, pattern):
        result = set()
        try:
            self.listen_output()
            await self.send_command(command)
            await wait()
            for l in self.output.splitlines():
                m = pattern.match(l)
                if m:
                    result.add(m.groups())
            return sorted(list(result), key=lambda i: i[1])
        finally:
            self.not_listen_output()

    async def list_devices(self):
        return await self.get_list('devices', DEVICE_PATTERN)

    async def list_paired_devices(self):
        return await self.get_list('paired-devices', DEVICE_PATTERN)

    async def list_controllers(self):
        return await self.get_list('list', CONTROLLER_PATTERN)

    async def select_paired_device(self):
        print('Selecting device:')
        devices = await self.list_paired_devices()
        count = len(devices)

        if count < 1:
            raise SubprocessError('There is no connected device.')
        elif count == 1:
            return devices[0]

        for i, d in enumerate(devices):
            print('%d. %s %s' % (i+1, d[0], d[1]))
        print('Select device[1]:')
        selected = input()
        return devices[0 if not selected.strip() else (int(selected) - 1)]


async def wait():
    return await asyncio.sleep(WAIT_TIME)


async def execute_command(cmd, ignore_fail=False):
    p = await asyncio.create_subprocess_shell(cmd, stdout=sb.PIPE, stderr=sb.PIPE)
    stdout, stderr = await p.communicate()
    stdout, stderr = \
        stdout.decode() if stdout is not None else '', \
        stderr.decode() if stderr is not None else ''
    if p.returncode != 0 or stderr.strip() != '':
        message = 'Command: %s failed with status: %s\nstderr: %s' % (cmd, p.returncode, stderr)
        if ignore_fail:
            print('Ignoring: %s' % message)
        else:
            raise SubprocessError(message)
    return stdout


async def execute_find(cmd, pattern, tries=0, fail_safe=False):
    tries = tries or TRIES

    message = 'Cannot find `%s` using `%s`.' % (pattern, cmd)
    retry_message = message + ' Retrying %d more times'
    while True:
        stdout = await execute_command(cmd)
        match = re.search(pattern, stdout)

        if match:
            return match.group()
        elif tries > 0:
            await wait()
            print(retry_message % tries)
            tries -= 1
            continue

        if fail_safe:
            return None

        raise RetryExceededError('Retry times exceeded: %s' % message)


async def find_dev_id(mac, **kw):
    return await execute_find('pactl list cards short', 'bluez_card.%s' % '_'.join(mac), **kw)


async def find_sink(mac, **kw):
    return await execute_find('pacmd list-sinks', 'bluez_sink.%s' % '_'.join(mac), **kw)


async def set_profile(device_id, profile):
    print('Setting the %s profile' % profile)
    try:
        return await execute_command('pactl set-card-profile %s %s' % (device_id, _profiles[profile]))
    except KeyError:
        print('Invalid profile: %s, please select one one of a2dp or hsp.' % profile, file=sys.stderr)
        raise SystemExit(1)


async def set_default_sink(sink):
    print('Updating default sink to %s' % sink)
    return await execute_command('pacmd set-default-sink %s' % sink)


async def move_streams_to_sink(sink):
    streams = await execute_command('pacmd list-sink-inputs | grep "index:"', True)
    for i in streams.split():
        i = ''.join(n for n in i if n.isdigit())
        if i != '':
            print('Moving stream %s to sink' % i)
            await execute_command('pacmd move-sink-input %s %s' % (i, sink))
    return sink


async def main(args):
    global WAIT_TIME, TRIES

    if args.version:
        print(__version__)
        return 0

    mac = args.mac

    # Hacking, Changing the constants!
    WAIT_TIME = args.wait
    TRIES = args.tries

    exit_future = asyncio.Future()
    transport, protocol = await asyncio.get_event_loop().subprocess_exec(
        lambda: BluetoothctlProtocol(exit_future, echo=args.echo), 'bluetoothctl'
    )

    try:

        if mac is None:
            mac, _ = await protocol.select_paired_device()

        mac = mac.split(':' if ':' in mac else '_')
        print('Device MAC: %s' % ':'.join(mac))

        device_id = await find_dev_id(mac, fail_safe=True)
        if device_id is None:
            print('It seems device: %s is not connected yet, trying to connect.' % ':'.join(mac))
            await protocol.trust(mac)
            await protocol.connect(mac)
            device_id = await find_dev_id(mac)

        sink = await find_sink(mac, fail_safe=True)
        if sink is None:
            await set_profile(device_id, args.profile)
            sink = await find_sink(mac)

        print('Device ID: %s' % device_id)
        print('Sink: %s' % sink)

        await set_default_sink(sink)
        await wait()

        await set_profile(device_id, 'off')

        if args.profile is 'a2dp':
            await protocol.disconnect(mac)
            await wait()
            await protocol.connect(mac)

        device_id = await find_dev_id(mac)
        print('Device ID: %s' % device_id)

        await set_profile(device_id, args.profile)
        await set_default_sink(sink)
        await move_streams_to_sink(sink)

    except (SubprocessError, RetryExceededError) as ex:
        print(str(ex), file=sys.stderr)
        return 1
    finally:
        print('Exiting bluetoothctl')
        await protocol.quit()
        await exit_future

        # Close the stdout pipe
        transport.close()

    if args.profile == 'a2dp':
        print('"Enjoy" the HiFi stereo music :)')
    else:
        print('"Enjoy" your headset audio :)')


if __name__ == '__main__':
    sys.exit(asyncio.get_event_loop().run_until_complete(main(parser.parse_args())))

Eu posso te dizer algumas coisas:

a) minha (pouca) experiência com bluetooth no linux diz que geralmente está quebrado; lá ou aqui eu sempre tenho algum tipo de problema.
b) bluez 4.99foi lançado em março de 2012, portanto, você está usando uma versão muito, muito antiga; Eu sugiro que você (se puder), pelo menos teste, uma versão mais recente.

Isso deve explicar seus problemas.