Bug#687045: pulseaudio: Audio delay and crackling at startup

[Felipe Sateler]

On Fri, Apr 18, 2014 at 8:15 PM, David Smith <sidicas2 at gmail.com> wrote:
> On 04/18/2014 06:01 PM, Felipe Sateler wrote:
>>
>> This may be a problem of too high CPU usage. Can you try changing the
>> resample-method key in daemon.pa?
>>
>> I think the 'trivial' resampler should be the less cpu-hungry, so you
>> should probably try that first.
>>
>
> That doesn't make any sense though, my laptop is an 8-core laptop that's
> sitting idle almost all the time when the crackling/popping happens.
>
> It *COULD* be something related to the frequency of my CPU changing..  I
> realized that the new intel power management stuff is clocking my CPU
> all over the place.. In the old days it would only cycle between 3 or 4
> different frequencies and it would be very slow about reclocking.. Now
> it's almost instantaneous reclocking of the CPU to save power and it's
> got a lot of different frequencies it can clock to..
>
> If I set my CPU to a fixed frequency, either the lowest or the highest
> possible frequency the CPU supports, the entire problem disappears.

Possibly the cpu frequency changes cause pulseaudio or alsa to loose sync.

>
> But I'm not going to run my CPU on a fixed frequency like that because
> it's always either inconveniently slow or a power hog.  So I need to use
> the configuration change to pulseaudio described above which seems to
> fix the problem entirely.

By the configuration change you mean the one I suggested or the tsched
one you suggested earlier in the bug report?


-- 

Saludos,
Felipe Sateler