[pulseaudio-discuss] Bluetooth devices no longer detected after upgrade from 2.0 to 4.0

[Georg Chini]

On 28.06.2013 08:23, Mikel Astiz wrote:
> Hi Georg,
>
> On Thu, Jun 27, 2013 at 1:31 PM, Georg Chini <georg at chini.tk> wrote:
>> On 27.06.2013 08:22, Mikel Astiz wrote:
>>> Hi Georg,
>>>
>>> On Wed, Jun 26, 2013 at 8:45 PM, Georg Chini <georg at chini.tk> wrote:
>>>> Hi Mikel,
>>>>
>>>>
>>>> On 26.06.2013 16:54, Mikel Astiz wrote:
>>>>> Hi Georg,
>>>>>
>>>>> On Wed, Jun 26, 2013 at 3:27 PM, Georg Chini <georg at chini.tk> wrote:
>>>>
>>>>>> Later on I decided to keep the modules around and just move them to the
>>>>>> right
>>>>>> source/sink when needed and move them to the default sound card and
>>>>>> mute
>>>>>> them when not in use.
>>>>> As a side suggestion, you probably want to use the profile
>>>>> availability to do this (if profile is available, it means 'playing').
>>>>>
>>>>>> The problem is that this does no longer work. Pavucontrol still shows
>>>>>> the
>>>>>> correct
>>>>>> sink/source but I do not get any sound when the modules are reused. It
>>>>>> seems
>>>>>> to be
>>>>>> a problem of resampling, the modules start to behave strangely as soon
>>>>>> as
>>>>>> sink and
>>>>>> source are moved the first time.
>>>>>> In the debug output I get endless repetition of:
>>>>>>
>>>>>> [alsa-sink-VT1828S Analog] module-loopback.c: Could not peek into queue
>>>>>> [alsa-sink-VT1828S Analog] module-loopback.c: Requesting rewind due to
>>>>>> end
>>>>>> of underrun.
>>>>>> [alsa-sink-VT1828S Analog] module-loopback.c: Requesting rewind due to
>>>>>> end
>>>>>> of underrun.
>>>>>> [alsa-sink-VT1828S Analog] module-loopback.c: Requesting rewind due to
>>>>>> end
>>>>>> of underrun.
>>>>>> [alsa-sink-VT1828S Analog] module-loopback.c: Requesting rewind due to
>>>>>> end
>>>>>> of underrun.
>>>>>>
>>>>>> The initial approach of using fresh modules each time the phone goes to
>>>>>> "playing" still
>>>>>> works fine.
>>>>> I think you hit a real issue here. I've experienced similar issues too
>>>>> at some point, but I can't reproduce it anymore.
>>>>>
>>>>> Can you tell us which exact states the source (assuming A2DP from the
>>>>> phone) and the source-output have? They should in theory be both in
>>>>> RUNNING state.
>>>> Sorry, I cannot find out. You can find a log of a complete session on
>>>> http://philipp.chini.tk/pulse/pulse-session.log
>>>> Maybe there is something useful in it. If not, please tell me how to get
>>>> the state of the source or what else I can do to locate the problem.
>>> You should use 'pactl list sources' and 'pactl list source-outputs',
>>> during the issue you describe about rewind requests.
>>>
>> All sources and source-outputs are in RUNNING state. The output
>> for the relevant module (now it's A2DP from the phone, so only one
>> module needed) looks like this:
>>      index: 6
>>          driver: <module-loopback.c>
>>          flags: START_CORKED
>>          state: RUNNING
> This looks good. Have you checked if the bar in pavucontrol shows some
> audio corresponding to this source?
>
>>          source: 2 <alsa_input.pci-0000_00_1b.0.analog-stereo>
>>          volume: 0: 100% 1: 100%
>>                  0: -0,00 dB 1: -0,00 dB
>>                  balance 0,00
>>          muted: yes
> Is it muted?
>
>>          current latency: 0,00 ms
>>          requested latency: 135,29 ms
>>          sample spec: s16le 2ch 44100Hz
>>          channel map: front-left,front-right
>>                       Stereo
>>          resample method: (null)
>>          owner module: 27
>>          properties:
>>                  media.role = "abstract"
>>                  module-stream-restore.id =
>> "source-output-by-media-role:abstract"
>>                  media.name = "Loopback to Internes Audio Analog Stereo"
>>                  media.icon_name = "audio-card-pci"
>>
>> Maybe the "resample method: (null)" is the problem?
> No, I don't think the resample method is relevant here. It also shows
> as null for me, and the audio just works.
>
> Cheers,
> Mikel
Hi Mikel,

after a bit of testing, I found an easy way to reproduce the problem.
It seems to occur when the phone is in "connected" state and you try
to move the source away from the loopback module. Pacmd shows the
bluetooth source as "SUSPENDED" while the source-output is "RUNNING".
Doing the following triggers the problem:

1) insert a loopback module with source=your_phone
2) wait until the phone is no longer playing
3) with pavucontrol move the source of the loopback module to another device

What is strange is that the messages start after the source has already 
changed.
I inserted a few log statements in module-loopback.c and got:

[bluetooth] module-loopback.c: Source Output detach 
bluez_source.00_12_D1_8C_FC_80
[pulseaudio] module-loopback.c: Source Output moving to 
alsa_input.pci-0000_00_1b.0.analog-stereo
[alsa-source-VT1828S Analog] module-loopback.c: Source Output attach 
alsa_input.pci-0000_00_1b.0.analog-stereo
[alsa-sink-USB Audio] module-loopback.c: Requesting rewind due to end of 
underrun.
[alsa-sink-USB Audio] module-loopback.c: Requesting rewind due to end of 
underrun.
...

Regards
              Georg