ao alsa is noisy since it was "unified"

[gabor@…]

i have an acer800laptop...it has an intel sound chip (users the
snd-intel8x0 alsa module).

i use from-cvs mplayer, with "-ao alsa".

before the alsa1x/alsa9 unification (when i used "alsa1x") everything went fine.

but now, with the unified 'alsa' driver,
i sometimes get noises into the video playback...

until now i could not reproduce them easily, but now i can :)

on my laptop i can adjust the brightness of the screen with
spec-laptop-key+left-arrow and spec-laptop-key+right-arrow.

now:
when using the cvs-current mplayer, when a video is played, and i play
with the brightness, i get a clicking sound all the time while the
brightness controlling keys are used.

it does not happen with the 'alsa1x' version.

it does not happen if i load oss emulation and use -ao oss

it does not happen with xine using alsa

it does not happen with totem using the gstreamer backend which uses
alsa.

[gabor@…]

btw. first bug, first bug :)))))

there's a relatively simple fix:

ao_alsa.c:

change
#undef SET_CHUNKSIZE

to
#define SET_CHUNKSIZE

that's how it was in the "alsa1x" alsa driver.

now the sound is perfect (again).

the only visible change i can see is:
with as-from-cvs-ao_alsa.c:(in the mplayer output)

alsa: 48000 Hz/2 channels/4 bpf/32768 bytes buffer/Signed 16 bit Little Endian

with the change i said here:

alsa: 48000 Hz/2 channels/4 bpf/65536 bytes buffer/Signed 16 bit Little Endian

i know the solution is not the cleanest (probably also the BUFFERTIME define
needs some adjustment to be programmatically correct), but it helps me.

[gabor@…]

this bugreport is more&less a cut&paste from

​http://mplayerhq.hu/pipermail/mplayer-users/2004-June/046185.html

[joy@…]

hopefully fixed in current cvs. chunksize ist set again so max buffersize is
asigned to ao_alsa.