[mythtv-users] Slow audio start

Jean-Yves Avenard jyavenard at gmail.com
Fri Apr 15 00:52:53 UTC 2011

On 15 April 2011 05:03, Jan Ceuleers <jan.ceuleers at gmail.com> wrote:

> Could it be the "use extra audio buffering" flag that might need to be
> turned off?

It wouldn't normally.

In fact extra audio buffering will be automatically activated if using
things like VDPAU.

Decoding audio doesn't take long, what slow down playback is always
the video decoding side of things, when you have to decode until you
hit a reference frame for example. This can take a short while.

With an analog output. Myth allocate an audio buffer aiming to be
500ms ; with your default 64kB of audio hardware buffer: for stereo,
16 bits, 48kHz that only gives you about 300ms of buffer. ALSA by
default is configured to start playback after it has buffered at least
1/16th of that time: so 18ms delay. Most wouldn't be able to perceive
that startup delay

Now, if using OSS it depends on the compatibility you are using. Which
is why I recommend you stop using OSS and try ALSA.

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