Same problem for me on Inspiron 1420 ... tried some of the suggestions in [url=https://bugs.launchpad.net/ubuntu/hardy/+source/linux/+bug/95940]this[/url] thread, but to no avail. Here is output of pulseaudio -vv:

shayne@shayne-laptop:~$ pulseaudio -vv
I: main.c: We're in the group 'pulse-rt', allowing real-time and high-priority scheduling.
I: core-util.c: Successfully gained nice level -11.
I: main.c: setrlimit(RLIMIT_NICE, (31, 31)) failed: Operation not permitted
I: main.c: setrlimit(RLIMIT_RTPRIO, (9, 9)) failed: Operation not permitted
I: main.c: Page size is 4096 bytes
I: main.c: Fresh high-resolution timers available! Bon appetit!
D: cli-command.c: Checking for existance of '/usr/lib/pulse-0.9/modules//module-hal-detect.so': success
I: module-hal-detect.c: Trying capability alsa
D: module-hal-detect.c: Not loaded device /org/freedesktop/Hal/devices/computer_alsa_timer
D: module-hal-detect.c: Not loaded device /org/freedesktop/Hal/devices/computer_alsa_sequencer
D: module-hal-detect.c: Loading module-alsa-sink with arguments 'device_id=0 sink_name=alsa_output.pci_8086_284b_sound_card_0_alsa_playback_0'
D: alsa-util.c: Trying front:0...
I: module-alsa-sink.c: Successfully opened device front:0.
I: module-alsa-sink.c: Successfully enabled mmap() mode.
ALSA lib control.c:909:(snd_ctl_open_noupdate) Invalid CTL front:0
I: alsa-util.c: Unable to attach to mixer front:0: No such file or directory
I: alsa-util.c: Successfully attached to mixer 'hw:0'
I: alsa-util.c: Cannot find mixer control "Master".
I: alsa-util.c: Using mixer control "PCM".
I: sink.c: Created sink 0 "alsa_output.pci_8086_284b_sound_card_0_alsa_playback_0" with sample spec "s16le 2ch 44100Hz"
I: source.c: Created source 0 "alsa_output.pci_8086_284b_sound_card_0_alsa_playback_0.monitor" with sample spec "s16le 2ch 44100Hz"
I: module-alsa-sink.c: Using 4 fragments of size 4352 bytes.
I: alsa-util.c: All 2 channels can be mapped to mixer channels. Using hardware volume control.
D: module-alsa-sink.c: Thread starting up
D: rtpoll.c: Acquired POSIX realtime signal SIGRTMIN+29
I: module-alsa-sink.c: Starting playback.
I: module.c: Loaded "module-alsa-sink" (index: #0; argument: "device_id=0 sink_name=alsa_output.pci_8086_284b_sound_card_0_alsa_playback_0").
D: module-hal-detect.c: Loading module-alsa-source with arguments 'device_id=0 source_name=alsa_input.pci_8086_284b_sound_card_0_alsa_capture_0'
D: alsa-util.c: Trying front:0...
I: module-alsa-source.c: Successfully opened device front:0.
I: module-alsa-source.c: Successfully enabled mmap() mode.
ALSA lib control.c:909:(snd_ctl_open_noupdate) Invalid CTL front:0
I: alsa-util.c: Unable to attach to mixer front:0: No such file or directory
I: alsa-util.c: Successfully attached to mixer 'hw:0'
I: alsa-util.c: Using mixer control "Capture".
I: source.c: Created source 1 "alsa_input.pci_8086_284b_sound_card_0_alsa_capture_0" with sample spec "s16le 2ch 44100Hz"
I: module-alsa-source.c: Using 4 fragments of size 4352 bytes.
I: alsa-util.c: All 2 channels can be mapped to mixer channels. Using hardware volume control.
D: module-alsa-source.c: Thread starting up
D: rtpoll.c: Acquired POSIX realtime signal SIGRTMIN+28
I: module.c: Loaded "module-alsa-source" (index: #1; argument: "device_id=0 source_name=alsa_input.pci_8086_284b_sound_card_0_alsa_capture_0").
D: module-hal-detect.c: Not loaded device /org/freedesktop/Hal/devices/pci_8086_284b_sound_card_0_alsa_control__1
I: module-hal-detect.c: Loaded 2 modules.
I: module.c: Loaded "module-hal-detect" (index: #2; argument: "").
I: module.c: Loaded "module-esound-protocol-unix" (index: #3; argument: "").
I: protocol-native.c: loading cookie from disk.
I: module.c: Loaded "module-native-protocol-unix" (index: #4; argument: "").
I: module.c: Loaded "module-volume-restore" (index: #5; argument: "").
D: module-default-device-restore.c: No previous default sink setting, ignoring.
D: module-default-device-restore.c: No previous default source setting, ignoring.
I: module.c: Loaded "module-default-device-restore" (index: #6; argument: "").
I: module.c: Loaded "module-rescue-streams" (index: #7; argument: "").
D: module-suspend-on-idle.c: Sink alsa_output.pci_8086_284b_sound_card_0_alsa_playback_0 becomes idle.
D: module-suspend-on-idle.c: Source alsa_output.pci_8086_284b_sound_card_0_alsa_playback_0.monitor becomes idle.
D: module-suspend-on-idle.c: Source alsa_input.pci_8086_284b_sound_card_0_alsa_capture_0 becomes idle.
I: module.c: Loaded "module-suspend-on-idle" (index: #8; argument: "").
D: cli-command.c: Checking for existance of '/usr/lib/pulse-0.9/modules//module-x11-publish.so': success
D: module-x11-publish.c: using already loaded auth cookie.
I: module.c: Loaded "module-x11-publish" (index: #9; argument: "").
D: cli-command.c: Checking for existance of '/usr/lib/pulse-0.9/modules//module-gconf.so': success
I: module.c: Loaded "module-gconf" (index: #10; argument: "").
I: main.c: Daemon startup complete.
D: module-hal-detect.c: dbus: interface=org.freedesktop.DBus, path=/org/freedesktop/DBus, member=NameAcquired
I: module-suspend-on-idle.c: Sink alsa_output.pci_8086_284b_sound_card_0_alsa_playback_0 idle for too long, suspending ...
I: module-alsa-sink.c: Device suspended...
I: module-suspend-on-idle.c: Source alsa_input.pci_8086_284b_sound_card_0_alsa_capture_0 idle for too long, suspending ...
I: module-alsa-source.c: Device suspended...
I: module-suspend-on-idle.c: Source alsa_output.pci_8086_284b_sound_card_0_alsa_playback_0.monitor idle for too long, suspending ...
D: module-hal-detect.c: dbus: interface=org.freedesktop.Hal.Device, path=/org/freedesktop/Hal/devices/acpi_BAT0, member=PropertyModified
D: module-hal-detect.c: dbus: interface=org.freedesktop.Hal.Device, path=/org/freedesktop/Hal/devices/acpi_BAT0, member=PropertyModified
D: module-hal-detect.c: dbus: interface=org.freedesktop.Hal.Device, path=/org/freedesktop/Hal/devices/acpi_BAT0, member=PropertyModified
D: module-hal-detect.c: dbus: interface=org.freedesktop.Hal.Device, path=/org/freedesktop/Hal/devices/acpi_BAT0, member=PropertyModified
D: module-hal-detect.c: dbus: interface=org.freedesktop.Hal.Device, path=/org/freedesktop/Hal/devices/acpi_BAT0, member=PropertyModified
D: module-hal-detect.c: dbus: interface=org.freedesktop.Hal.Device, path=/org/freedesktop/Hal/devices/acpi_BAT0, member=PropertyModified