On 03/28/2014 10:49 AM, Andrea M wrote: > I bought an USB DAC from TEAC (device UD-H01 with chip TENOR 8802) and this, > with its own drivers, works perfectly under Windows7 and OSX ( I tried both > with 16 and 24 bit from 44.1 to 192Khz). > On my netbook which has Linux Mint last version and driver ALSA last > version, it works only at 16bit. While at 24bit, whatever is the frequency, > the sound is distorted and with many "clicks". I've been running into similar issues with a TEAC amp (AI501DA) which embeds a USB DAC (PCM5102). Well, the word "issue" may be inappropriate in my case, as I am using this device in an HTPC scenario, mostly sending 16/44 content to it so I have not investigated any time tracking that down, but I did witness the same phenomenon playing with 24/192(*) content. I made the following observations: - whatever the kernel - with sox/aplay sending raw content to the ALSA device - 24/192 content is subject to very high jitter/cracks. - interestingly, I've noticed that xbmc (7a6cb7f) plays 24/192 content correctly if the kernel is <= 3.12. With more recent versions (tried 3.13 and mainline about 2 weeks ago), playing the content leads to the same jitter/cracks in xbmc. - Now When xbmc plays 24/192 content correctly, all I know is that /proc/asound/card/*/stream* confirms that the steam is 24/192, but xbmc must be either doing something to the stream, or streaming it a little bit differently than sox/aplay. - Last but not least, and to make the issue more fun to investigate, arch's stock xbmc (12.3-12), or version 13.0 (with pulseaudio totally turned off) never play 24/192 content without jitter/cracks. - options snd-usb-audio nrpacks=1 makes no difference *: more precisely, anything with 24-bit depth and a frequency greater than 48khz. -- Julien Benoist ------------------------------------------------------------------------------ _______________________________________________ Alsa-user mailing list Alsa-user@xxxxxxxxxxxxxxxxxxxxx https://lists.sourceforge.net/lists/listinfo/alsa-user
