On Sun, 16 Feb 2014, Samuele Carcagno wrote: > Hi, > > I'm trying to set up the e-mu 0204 for psychoacoustics research purposes on Debian Wheezy. > When using aplay to play a short (200 ms, or 900 ms) wav file, at the onset and at the offset of the sound > there are audible pops and clicks. I'm actually using a GUI program I wrote in pyqt4 that writes the sound > to a wav file, and then calls aplay to play it. This program can also output sound through PyAudio (portaudio) and > pyalsaaudio. If I play a sound with PyAudio, then there are no pops and clicks at the onset/offset of the You could route the output into the line in input, and record what is coming out of the system and compare it with what you sent. Now you do not expect bit accuracy but you might be able to see something going on. Eg, a DC level mismatch. > sound, however, with PyAudio there are occasional distortions in the middle of the sound. > The strange thing is that if I first play some sounds with PyAudio and then switch to aplay, aplay > works well without pops and clicks at the onset/offset of the sound. I have the impression that PyAudio > is setting some soundcard parameters that make it work well with aplay. If I close the pyqt4 GUI and > open it again, the problem with aplay returns. Do you have any idea of what the problem could be, > and how it could be fixed? > > Some additional info. The problem with aplay is present also if I use it from the command line rather > than the pyqt4 app. pyalsaaudio has the same problem as aplay, again if I play some sounds with PyAudio > and then switch to aplay the problem is fixed, as long as I keep the pyqt4 app open. I have been using > the same program with the e-mu 0202 and it has been working without any issues, so I would discard the pyqt4 > app as the source of the program. I have tried plugging the 0204 on different USB ports but the problem persists. > > Thank you for your help, > > Sam > > ------------------------------------------------------------------------------ > Android apps run on BlackBerry 10 > Introducing the new BlackBerry 10.2.1 Runtime for Android apps. > Now with support for Jelly Bean, Bluetooth, Mapview and more. > Get your Android app in front of a whole new audience. Start now. > http://pubads.g.doubleclick.net/gampad/clk?id=124407151&iu=/4140/ostg.clktrk > _______________________________________________ > Alsa-user mailing list > Alsa-user@xxxxxxxxxxxxxxxxxxxxx > https://lists.sourceforge.net/lists/listinfo/alsa-user > -- William G. Unruh | Canadian Institute for| Tel: +1(604)822-3273 Physics&Astronomy | Advanced Research | Fax: +1(604)822-5324 UBC, Vancouver,BC | Program in Cosmology | unruh@xxxxxxxxxxxxxx Canada V6T 1Z1 | and Gravity | www.theory.physics.ubc.ca/ ------------------------------------------------------------------------------ Android apps run on BlackBerry 10 Introducing the new BlackBerry 10.2.1 Runtime for Android apps. Now with support for Jelly Bean, Bluetooth, Mapview and more. Get your Android app in front of a whole new audience. Start now. http://pubads.g.doubleclick.net/gampad/clk?id=124407151&iu=/4140/ostg.clktrk _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user
