Banshee won't play M4a

[Nils Durner]

When Banshee encounters an m4a file, it displays an error message saying that it cannot find an extension for playback.
Debug log:
---
[1 Debug 22:09:34.984] (libbanshee:player) Saving missing element details ('gstreamer|0.10|Banshee|MPEG-4 AAC demuxer|decoder-audio/x-m4a')
[1 Debug 22:09:34.985] (libbanshee:player) bp_stop: setting state to GST_STATE_NULL
[1 Debug 22:09:34.986] Player state change: Loading -> Idle
....
[1 Debug 22:09:35.829] (libbanshee:player) Ignoring missing element details, already prompted ('gstreamer|0.10|Banshee|MPEG-4 AAC demuxer|decoder-audio/x-m4a')
[1 Debug 22:09:35.830] (libbanshee:player) bp_stop: setting state to GST_STATE_NULL
---

$ sudo dpkg --get-selections | grep gst
bluez-gstreamer install
gstreamer0.10-alsa install
gstreamer0.10-ffmpeg install
gstreamer0.10-fluendo-mp3 install
gstreamer0.10-gnomevfs install
gstreamer0.10-gnonlin install
gstreamer0.10-nice install
gstreamer0.10-plugins-bad install
gstreamer0.10-plugins-bad-multiverse install
gstreamer0.10-plugins-base install
gstreamer0.10-plugins-base-apps install
gstreamer0.10-plugins-good install
gstreamer0.10-plugins-ugly install
gstreamer0.10-pulseaudio install
gstreamer0.10-tools install
gstreamer0.10-x install
libgstfarsight0.10-0 install
libgstreamer-plugins-base0.10-0 install
libgstreamer0.10-0 install
libgstrtspserver-0.10-0 install
python-gst0.10 install

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Asa Berkley (asa-berkley)]

I think I had the same problem. Ever since updating to Oneiric I hadn't been able to view any videopodcasts (m4v) in Banshee.
Apparently it's related to this bug: https://bugs.launchpad.net/ubuntu/+source/gstreamer0.10/+bug/856988
The solution provided there by user aortega [rm -r ~/.gstreamer-0.10] resolved this for me. :)

[Nils Durner (ndurner)]

Upgrading to Oneiric fixed it for me.