=== update Jan 26 ===
Patch accepted in upstream sound, should be in next 4.5-rc2 and next stable vanilla kernel starting from 4.5.
I bought a fresh Teac UD-503 yesterday and it was driving me crazy last evening, always disconnecting/freezing when switching from S16 to S32 format, or simply changing file rate.
I was also getting the same “clock source 41 is not valid, cannot use” as the UD-501. Error i never took time to check because it was working.
So, here is a patch i have make this morning to correct these bugs with these high-end/high-rec dacs and allow bit-perfect mode.
It is a simple delay to append. After my tests, it seems quite similar to the patch for the “Playback Design” products.
Now everything works perfectly:
– no clock error anymore
– no freeze with the dac usb interface
– seamless switch between format/rate or PCM/DSD mode.
The patch is small and generic, tested on kernel 4.3.0 and current mainline 4.4, should work on every >=3.x with some ajustement in lines.
Under debian, you will only need to recompile the kernel module:
---- NEEDED PACKAGES (replace x.y.z-n in context and switch between amd64 or i386 if needed) # apt-get install build-essential linux-source-x.y linux-headers-amd64 ---- PREPARE THE SOURCE # cd /usr/src/ # tar xf linux-source-x.y.tar.xz # cd linux-source-x.y # wget -qO- /wp-content/uploads/2016/01/snd-usb-quirks-patch-teac.patch_.gz | gunzip | patch -p0 ---- PREPARE TO COMPILE # cp /boot/config-x.y.z-n .config # make oldconfig # cp /usr/src/linux-headers-x.y.z-n/Module.symvers . # make prepare ---- DEP problems - just run this shortly to get scripts/recordmcount compiled and once passed, CTRL-C # make ---- Compile the module # make M=sound/usb ---- Load the patched module # rmmod snd-usb-audio # insmod sound/usb/snd-usb-audio.ko ---- Test, enjoy ---- Make it permanent # cp -a sound/usb/snd-usb-audio.ko /lib/modules/x.y.z-n/kernel/sound/usb/ # depmod -a # rmmod snd-usb-audio # modprobe snd-usb-audio