** Description changed: - In Intrepid and Jaunty, audio sent through the Plantronics DA40 is - distorted if the per-application volume is above around 80%. - Unfortunately, all applications default to 100%. Audio sent directly to - the ALSA device is not distorted, so this is something happening in - pulseaudio. I attempted to test this under Karmic, but the volume - sliders behave very differently, with the pavucontrol sliders adjusting - the ALSA "Speaker" mixer, and I was unable to remove the distortion at - all. + [SRU Justification] + Impact: See below. But in short, distorted sound when on an analog-mono profile. Most soundcards support analog-stereo only, but for some hardware, this is a problem. + + Testcase: Using hardware that supports analog-mono profile, play back audio, source + material at sufficient volume. If this bug is fixed, there is no distortion. + + Regression potential: Can't think of any, and if so, it should only + affect downmixing to mono, which is unusual anyway. + + + In Intrepid and Jaunty, audio sent through the Plantronics DA40 is distorted if the per-application volume is above around 80%. Unfortunately, all applications default to 100%. Audio sent directly to the ALSA device is not distorted, so this is something happening in pulseaudio. I attempted to test this under Karmic, but the volume sliders behave very differently, with the pavucontrol sliders adjusting the ALSA "Speaker" mixer, and I was unable to remove the distortion at all. The DA40 is a mono device, so perhaps it's a problem with pulse downmixing stereo audio to mono without reducing the per-channel level, resulting in clipping. but I tested with a DA45, which is a similar mono adapter, and the problem didn't exist.
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/416190 Title: Pulseaudio produces overdriven audio on mono downmix (e g to Plantronics DA40 adapter) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/416190/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
