Arch Linux

nawitus

Member

Registered: 2009-05-11

Posts: 112

Video and audio not in sync (ALSA underrun occurred)

Hi, after a recent system upgrade (upgrade log here http://pastebin.com/1gRwexFr), video and sound are not in sync anymore. The problem occurs in mplayer instantly, and in XBMC after a while (the audio is slowly getting out of sync). The error message I get continuously in XBMC is "ALSA lib pcm.c:7339:(snd_pcm_recover) underrun occurred". The error I get in mplayer is "[ac3 @ 0xf46b40]frame sync error" I did another system upgrade and the problem persists. I'm using Terratec Aureon 7.1 external sound card and linux 3.3.3-1-ARCH. I'm not using pulseaudio, just alsa.

EDIT: I downgraded (sudo pacman -U linux-3.2.13-1-x86_64.pkg.tar.xz linux-headers-3.2.13-1-x86_64.pkg.tar.xz linux-api-headers-3.1.6-1-x86_64.pkg.tar.xz dbus-1.4.16-1-x86_64.pkg.tar.xz dbus-core-1.4.16-1-x86_64.pkg.tar.xz glibc-2.15-7-x86_64.pkg.tar.xz) and the problem seems to be gone. I'm suspecting the kernel upgrade broke it..

Last edited by nawitus (2012-05-02 20:08:53)

brebs

Member

Registered: 2007-04-03

Posts: 3,742

Re: Video and audio not in sync (ALSA underrun occurred)

underrun occurred

See what buffer size you end up with. Start mplayer, and run:

cat /proc/asound/card0/pcm0p/sub0/hw_params