Comment 10 for bug 422451

Backtrace:

(gdb) cont
Continuing.

Program received signal SIG63, Real-time event 63.
[Switching to Thread 0xb7e01b70 (LWP 30474)]
0x00aa1424 in __kernel_vsyscall ()
(gdb) bt
#0 0x00aa1424 in __kernel_vsyscall ()
#1 0x006bd470 in ppoll (fds=0x8aeca28, nfds=3, timeout=0xb7e011f4,
    sigmask=0x8ade7d8) at ../sysdeps/unix/sysv/linux/ppoll.c:58
#2 0x0059a49c in pa_rtpoll_run (p=0x8ade7b8, wait=true)
    at pulsecore/rtpoll.c:413
#3 0x00fdd2c3 in thread_func (userdata=0x8ade610)
    at modules/alsa/alsa-sink.c:1347
#4 0x0309979c in internal_thread_func (userdata=0x8af29b8)
    at pulsecore/thread-posix.c:72
#5 0x00c1a935 in start_thread (arg=0xb7e01b70) at pthread_create.c:297
#6 0x006c793e in clone () at ../sysdeps/unix/sysv/linux/i386/clone.S:130
(gdb) cont
Continuing.

Program received signal SIG62, Real-time event 62.
[Switching to Thread 0xb324eb70 (LWP 30475)]
0x00aa1424 in __kernel_vsyscall ()
(gdb) cont
Continuing.

Program received signal SIG62, Real-time event 62.
0x00aa1424 in __kernel_vsyscall ()
(gdb) cont
Continuing.

Program received signal SIG62, Real-time event 62.
0x00aa1424 in __kernel_vsyscall ()
(gdb) cont
Continuing.

Program received signal SIG62, Real-time event 62.
0x00aa1424 in __kernel_vsyscall ()
(gdb) cont
Continuing.

Program received signal SIG62, Real-time event 62.
0x00aa1424 in __kernel_vsyscall ()
(gdb) cont
Continuing.

Program received signal SIG62, Real-time event 62.
0x00aa1424 in __kernel_vsyscall ()
(gdb) cont
Continuing.

Program received signal SIGABRT, Aborted.
[Switching to Thread 0xb8002750 (LWP 30473)]
0x00aa1424 in __kernel_vsyscall ()
(gdb) bt
#0 0x00aa1424 in __kernel_vsyscall ()
#1 0x006147c1 in *__GI_raise (sig=6)
    at ../nptl/sysdeps/unix/sysv/linux/raise.c:64
#2 0x00616092 in *__GI_abort () at abort.c:88
#3 0x005c39e0 in pa_source_set_volume (s=0x8afc738, volume=0xbfe18e68)
    at pulsecore/source.c:666
#4 0x0024c3a7 in command_set_volume (pd=0x8af7c68, command=38, tag=5413,
    t=0x8adedb0, userdata=0x8ade008) at pulsecore/protocol-native.c:3327
#5 0x03083298 in pa_pdispatch_run (pd=0x8af7c68, packet=0x8ae0e00,
    creds=0x8ade440, userdata=0x8ade008) at pulsecore/pdispatch.c:326
#6 0x0024fdd9 in pstream_packet_callback (p=0x8ade378, packet=0x8ae0e00,
    creds=0x8ade440, userdata=0x8ade008) at pulsecore/protocol-native.c:4234
#7 0x03089317 in do_read (p=0x8ade378) at pulsecore/pstream.c:816
#8 0x03086a99 in do_something (p=0x8ade378) at pulsecore/pstream.c:184
#9 0x03086cbb in io_callback (io=0x8adc838, userdata=0x8ade378)
    at pulsecore/pstream.c:213
#10 0x03070885 in callback (m=0x8ab2b44, e=0x8addfd8, fd=8, f=3,
    userdata=0x8adc838) at pulsecore/iochannel.c:119
#11 0x030cdd91 in dispatch_pollfds (m=0x8ab2b08) at pulse/mainloop.c:683
#12 0x030ceaa1 in pa_mainloop_dispatch (m=0x8ab2b08) at pulse/mainloop.c:896
#13 0x030cec32 in pa_mainloop_iterate (m=0x8ab2b08, block=1, retval=0xbfe19300)
    at pulse/mainloop.c:926
#14 0x030cec98 in pa_mainloop_run (m=0x8ab2b08, retval=0xbfe19300)
    at pulse/mainloop.c:941
#15 0x080548e2 in main (argc=3, argv=0xbfe19414) at daemon/main.c:1054

further info:
(gdb) p volume
$1 = (const pa_cvolume *) 0xbfe18e68
(gdb) p *volume
$2 = {channels = 1 '\1', values = {2, 145624656, 7697280, 3219230408,
    50862238, 51043024, 7697292, 3219230424, 145616304, 51043088, 51040728,
    3219230392, 50934985, 20, 2435490, 0, 145622760, 6665534, 51040728,
    3219230472, 50935184, 1, 20, 3219230472, 50941295, 622133248, 145624598,
    4, 2362281, 2434851, 1, 3219230520}}
(gdb) p s->sample_spec
$3 = {format = PA_SAMPLE_S16LE, rate = 44100, channels = 2 '\2'}

Rough guess: the channel count does not match ?