On Sun, 2008-06-08 at 23:07 +0200, Lennart Poettering wrote: > On Wed, 04.06.08 20:07, James Bottomley (James.Bottomley at HansenPartnership.com) wrote: > > > I suspect this is some type of resampler problem rather than an actual > > connection problem. The headset is a GN6210H (which is a phone headset, > > so mono earpiece and mono mic). The only other oddity is that apart > > from having only one channel, its sample rate is 8000Hz. > > > > I have it all correctly plumbed into alsa using bluez and if I just use > > alsa, I can send sound to it with mplayer using > > > > mplayer -ao alsa:device=headset > > > > Since mplayer sees the device directly, it sends the sound stream as > > > > AO: [alsa] 800Hz 1ch s16le (2 bytes per sample) > > 800? Uh? Transcription error; should be 8000Hz > > And everything sounds fine. > > > > When I plug it into pulseaudio with > > > > pactl load-module module-alsa-sink device=headset > > > > It correctly picks up the sample rate and channels. However, trying to > > switch an application to it results in dramatic speed increases and the > > output being chopped to pieces. If I set up pulseaudio only to have > > this device and nothing else, mplayer plays the sound file at at least > > 2x the usual speed. > > > > Since the output has this: > > > > AO: [pulse] 44100Hz 2ch s16le (2 bytes per sample) > > > > I suspect the problem is somewhere in the pulseaudio resampling down > > from 2 channels at 44100Hz to a single channel at 8000Hz. I've tried > > forcing different resampling methods with slightly different sounding > > results but still playing at at least 2x the speed. > > The current BT for ALSA code is not really that good for doing > timing. Which is mostly BT's fault, not ALSAs or the driver's > code. We're working on some better way to directly hook up BT with PA, > which will hopefully also allows us to do fancier timing/latency estimation: > > See > https://tango.0pointer.de/pipermail/pulseaudio-discuss/2008-June/001909.html > for more details. > > I don't have no SCO device, so my priority right now is to get PA/BT > to play together directly, instead of trying to fix the > PA-on-ALSA-on-BT mess working. Hmm, OK ... it is strange that alsa by itself works fine ... it just doesn't work with pulsaudio -> alsa. James
