in gnome-mplayer preferences i have not check "Mplayer Software Volume Control Enabled" but when i change audio it change master audio Reproducible: Always Portage 2.1.6.13 (default/linux/amd64/2008.0/desktop, gcc-4.3.2, glibc-2.9_p20081201-r2, 2.6.29-gentoo-r5 x86_64) ================================================================= System uname: Linux-2.6.29-gentoo-r5-x86_64-Pentium-R-_Dual-Core_CPU_E5200_@_2.50GHz-with-glibc2.2.5 Timestamp of tree: Thu, 02 Jul 2009 22:45:02 +0000 app-shells/bash: 3.2_p39 dev-lang/python: 2.5.4-r2 dev-util/cmake: 2.6.4 sys-apps/baselayout: 1.12.11.1 sys-apps/sandbox: 1.6-r2 sys-devel/autoconf: 2.13, 2.63 sys-devel/automake: 1.5, 1.7.9-r1, 1.9.6-r2, 1.10.2 sys-devel/binutils: 2.18-r3 sys-devel/gcc-config: 1.4.1 sys-devel/libtool: 1.5.26 virtual/os-headers: 2.6.27-r2 ACCEPT_KEYWORDS="amd64" CBUILD="x86_64-pc-linux-gnu" CFLAGS="-march=native -O2 -pipe" CHOST="x86_64-pc-linux-gnu" CONFIG_PROTECT="/etc" CONFIG_PROTECT_MASK="/etc/ca-certificates.conf /etc/env.d /etc/fonts/fonts.conf /etc/gconf /etc/php/apache2-php5/ext-active/ /etc/php/cgi-php5/ext-active/ /etc/php/cli-php5/ext-active/ /etc/revdep-rebuild /etc/sandbox.d /etc/terminfo /etc/texmf/language.dat.d /etc/texmf/language.def.d /etc/texmf/updmap.d /etc/texmf/web2c /etc/udev/rules.d" CXXFLAGS="-march=native -O2 -pipe" DISTDIR="/usr/portage/distfiles" EMERGE_DEFAULT_OPTS="--keep-going --with-bdeps y" FEATURES="distlocks fixpackages parallel-fetch protect-owned sandbox sfperms strict unmerge-orphans userfetch" GENTOO_MIRRORS="http://distfiles.gentoo.org http://distro.ibiblio.org/pub/linux/distributions/gentoo" LANG="en_US.UTF-8" LDFLAGS="-Wl,-O1" MAKEOPTS="-j3" PKGDIR="/usr/portage/packages" PORTAGE_CONFIGROOT="/" PORTAGE_RSYNC_OPTS="--recursive --links --safe-links --perms --times --compress --force --whole-file --delete --stats --timeout=180 --exclude=/distfiles --exclude=/local --exclude=/packages" PORTAGE_TMPDIR="/var/tmp" PORTDIR="/usr/portage" SYNC="rsync://rsync.europe.gentoo.org/gentoo-portage" USE="X acl acpi alsa amd64 berkdb bluetooth branding bzip2 cairo cdr cli cracklib crypt cups dbus dri dvd dvdr dvdread eds emboss encode esd evo fam firefox fortran gdbm gif gnome gpm gstreamer gtk hal iconv ipv6 isdnlog jpeg ldap libnotify mad midi mikmod mmx mp3 mpeg mudflap multilib nautilus ncurses nls nptl nptlonly nsplugin ogg opengl openmp pam pcre pdf perl png ppds pppd python quicktime readline reflection samba sdl session spell spl sse sse2 ssl startup-notification svg sysfs tcpd tiff truetype unicode usb vorbis xml xorg xulrunner xv zlib" ALSA_CARDS="ali5451 als4000 atiixp atiixp-modem bt87x ca0106 cmipci emu10k1x ens1370 ens1371 es1938 es1968 fm801 hda-intel intel8x0 intel8x0m maestro3 trident usb-audio via82xx via82xx-modem ymfpci" ALSA_PCM_PLUGINS="adpcm alaw asym copy dmix dshare dsnoop empty extplug file hooks iec958 ioplug ladspa lfloat linear meter mmap_emul mulaw multi null plug rate route share shm softvol" APACHE2_MODULES="actions alias auth_basic authn_alias authn_anon authn_dbm authn_default authn_file authz_dbm authz_default authz_groupfile authz_host authz_owner authz_user autoindex cache dav dav_fs dav_lock deflate dir disk_cache env expires ext_filter file_cache filter headers include info log_config logio mem_cache mime mime_magic negotiation rewrite setenvif speling status unique_id userdir usertrack vhost_alias" ELIBC="glibc" INPUT_DEVICES="keyboard mouse evdev" KERNEL="linux" LCD_DEVICES="bayrad cfontz cfontz633 glk hd44780 lb216 lcdm001 mtxorb ncurses text" USERLAND="GNU" VIDEO_CARDS="nvidia nv vesa" Unset: CPPFLAGS, CTARGET, FFLAGS, INSTALL_MASK, LC_ALL, LINGUAS, PORTAGE_COMPRESS, PORTAGE_COMPRESS_FLAGS, PORTAGE_RSYNC_EXTRA_OPTS, PORTDIR_OVERLAY
Upstream issue, report to http://code.google.com/p/gnome-mplayer and provide a link here.
don't know why, but after some update (don't know wich package in particular) this problem is vanish
