[alsa-devel] ALSA 1.0.25 broke AC3 passthrough?

Jean-Yves Avenard jyavenard at gmail.com
Sat Feb 11 11:41:21 CET 2012


Hi

On 10 February 2012 15:09, Stephen Warren <swarren at nvidia.com> wrote:

> You'd mentioned that this problem was present in ALSA 1.0.25, but wasn't
> in some earlier release. Potentially a lot changed between those two
> releases. It'd be nice if you could try compiling a number of
> intermediate versions of the ALSA driver to try and more precisely
> locate the change that caused the issue. "git bisect" on the ALSA driver
> repository might be useful here.

Ok...

This is interesting..

Compiling from git, using tag v1.0.25, the problem is there...
Compiling master, it's not

However, the issue doesn't show with v1.0.25, when the ALSA hardware
buffer is set to its default 64kB.
If I set it to a higher value (echo 4096 | sudo tee
/proc/asound/card1/pcm3p/sub0/prealloc) ; then it shows up.

so obviously the issue has been fixed between the time 1.0.25 was
released, and now.

I will try to identify which change between 1.0.24 and 1.0.25 broke it
however... Which would lead precisely to which change in master fixed
it. So a 1.0.25.2 can be released soon fixing that problem..

JY


More information about the Alsa-devel mailing list