On 12.12.2012 22:20, Thorsten Mühlfelder wrote: >>> Problems left: * There is a blob at the beginning of playback >> >> This is most probably a bug in the hardware chain somewhere. Can >> you exclude the possibilty that this plop is produced by the >> receiving side and occurs every time the link was lost? You can >> try that by re-plugging the optical cable while audio is >> streaming. > > Replugging the optical cable does not produce any plops or noise. > Also the same connection with my PCI sound card works fine. Also > I've noticed that the plops aren't always there and vary in volume. > Furthermore mpd even produces some noise when pressing stop. Then try with aplay and stream a file that is guaranteed not to have any plopp at the beginning. Might just really be a user space bug then, as I'm not aware of any such issue in the driver. >> This is a known bug, also most probably flaw in the CMEDIA chip, >> and not yet properly worked around in the snd-usb driver. If you >> want to investigate, have a look at the feedback format >> autodetection code in sound/usb/endpoint.c. > > Thanks, I'll have a look. I believe what's going on here is that the device is confused after sample rate changes and keeps sending back feedback data for the old rate on its feedback endpoint. That causes the autodetection algorithm, which kicks in on every first packet of a stream, to go nuts, which causes the part of the driver that sends the data assume a very wrong rate. Some printk() there should give you a hint. Daniel ------------------------------------------------------------------------------ LogMeIn Rescue: Anywhere, Anytime Remote support for IT. Free Trial Remotely access PCs and mobile devices and provide instant support Improve your efficiency, and focus on delivering more value-add services Discover what IT Professionals Know. Rescue delivers http://p.sf.net/sfu/logmein_12329d2d _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user
