I have an M-Audio Fast Track Pro which I would to like to use for audio capture. I've been testing audio capture using the following command: $ arecord -f dat -D hw:0,1 | aplay -f dat I am finding that ALSA has some issues a far as the Fast Track Pro is concerned: - Roughly 80% of the time, audio capture works. - In about 15% of cases, the captured signal suffers extreme digital distortion. - In the remaining ~5% of cases, the captured signal isn't clipping, but it sounds like there is quite a bit of quantization distortion (i.e., it sounds like it was recorded in 8 bit). Once I get a distorted signal, all subsequent invocations of arecord produce a similarly distorted signal. The only way I have found to make the problem go away, at least temporarily, is to power-cycle the device. Note that the distortion doesn't occur mid-stream; a capture is either all good or all bad. This leads me to suspect that ALSA is improperly initializing the Fast Track Pro, but I am not sure why this results in a distorted signal only some of the time. Audio capture seems to work well when using the device under Windows, so I don't think my hardware is defective. Additionally, after raising the issue on the linux-audio-user mailing list, other Fast Track Pro users have reported a similar issue with the ALSA driver. I'm hoping those more knowledgeable than myself might be able to steer me in the right direction here. I would be more than happy to contribute my time to help debug and test any possible solutions in order to improve the current driver. .lewis ------------------------------------------------------------------------------ WatchGuard Dimension instantly turns raw network data into actionable security intelligence. It gives you real-time visual feedback on key security issues and trends. Skip the complicated setup - simply import a virtual appliance and go from zero to informed in seconds. http://pubads.g.doubleclick.net/gampad/clk?id=123612991&iu=/4140/ostg.clktrk _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user
