[pulseaudio-discuss] Pulseaudio sound quality problem on ARM

[Arun Raghavan]

On 28 October 2014 15:09, Andrej Šimko <andrej.simko at gmail.com> wrote:
> Hello everybody,
>
> we have problem with quality of sound with pulseaudio used with
> freeswitch with portaudio modul, which gets worse(crackling) after
> random time (couple of hours). When we restart pulseaudio with our own
> script (in attachment pulseaudio-restart and pulseaudio-restore)
> everything gets back to normal. Everything is running on gentoo and
> installed like this:
> [I] media-sound/pulseaudio
>      Available versions:  [M]2.1-r1 [M]4.0 5.0-r2 (~)5.0-r3 {+X +alsa
> +asyncns avahi bluetooth +caps dbus doc equalizer +gdbm +glib gnome gtk
> ipv6 jack libsamplerate lirc neon +orc oss qt4 realtime ssl system-wide
> systemd tcpd test +udev +webrtc-aec xen zeroconf ABI_MIPS="n32 n64 o32"
> ABI_PPC="32 64" ABI_S390="32 64" ABI_X86="32 64 x32"}
>      Installed versions:  5.0-r3(11:07:32 AM 10/21/2014)(X alsa asyncns
> bluetooth caps dbus equalizer gdbm glib gnome libsamplerate neon qt4
> realtime ssl tcpd udev webrtc-aec -doc -gtk -ipv6 -jack -lirc -orc -oss
> -system-wide -systemd -test -xen -zeroconf ABI_MIPS="-n32 -n64 -o32"
> ABI_PPC="-32 -64" ABI_S390="-32 -64" ABI_X86="-32 -64 -x32")
>      Homepage:            http://www.pulseaudio.org/
>      Description:         A networked sound server with an advanced
> plugin system
>
> Our hardware: Olimex A20
> Cpu info:
> Processor    : ARMv7 Processor rev 4 (v7l)
> processor    : 0
> BogoMIPS    : 954.36
>
> processor    : 1
> BogoMIPS    : 957.64
>
> Features    : swp half thumb fastmult vfp edsp neon vfpv3 tls vfpv4
> idiva idivt
> CPU implementer    : 0x41
> CPU architecture: 7
> CPU variant    : 0x0
> CPU part    : 0xc07
> CPU revision    : 4
>
> Hardware    : sun7i
> Revision    : 0000
> Serial        : 0000000000000000
>
> /etc/pulseaudio/daemon.conf ... in attachment
> /etc/pulse/default.pa  ... in attachment
> users .pulse/default.pa ... in attachment
> pacmd info output ... in attachment
>
> We tried, to change aec method from speex to webrtc, only difference is,
> that cpu "eats" 5% less with speex. We tried also tsched=0, but it gets
> worse ...
> Does anybody know how to solve this and have clear sound all the time?
> Problem is with pulseaudio, that we know for sure, we have the same
> exactly setup on 6 pc's in different locations.

It's really hard to say with this information. One thing I'd be
interested in knowing is whether this happens with the echo-cancel
module is not loaded. Either way, having verbose daemon logs would be
the first step to trying to figure out where things go wrong.

-- Arun

p.s.: You probably don't really want to use the speex canceler if the
webrtc one works at all.