On Thu, 2013-01-31 at 17:04 +0100, David Henningsson wrote: > [Adding Arun, Liam and Feng to CC] > > On 01/30/2013 12:15 PM, Luke Yelavich wrote: > > Got it thanks, applied along with using alsa 1.0.26. > > > > However, it seems we have another one, and this has produced another, bigger stacktrace, which is attached. Still the PandaBoardES with the same UCM config I sent to the list. > > > > This looks like: https://bugs.freedesktop.org/show_bug.cgi?id=53036 Yep. > But can we reconfirm that "PlaybackChannels" or "CaptureChannels" are > really required? Required in what sense? UCM itself doesn't require those, but the current pulseaudio code requires those values (the assertion is there for a reason). It's of course possible to change pulseaudio code if you feel like it, but I think it would make useful to improve those configuration files. > None of the files Ubuntu ships today have it, and AFAIU > it has not been required in the past (i e PA 2.1). Is there any > documentation of this, so if it really is required, we know how to add it? PA 2.1 didn't have UCM support. I don't know why Ubuntu ships any UCM configuration files at all, if they have never been tested (at least not with PulseAudio). I'm not aware of any documentation (apart from the little[1] that I started to write and never finished). This is how you define PlaybackChannels for a device in the UCM configuration: SectionDevice."speakers-output" { ... Value { PlaybackPCM "hw:RX51,0" PlaybackChannels "2" } } Here is an example of configuration that has been confirmed to work with PulseAudio: [2]. [1] http://www.alsa-project.org/main/index.php/Use_Case_Manager [2] https://gitorious.org/~tanuk2/alsa/tanuk2s-alsa-lib/commit/53d1042d80ac73d8809fa3f9ee1308682a51c7bc -- Tanu