On Thu, May 5, 2011 at 9:07 PM, jegunn <[email protected]> wrote: >... > USB1 mode does not work with any recent Linux kernel or any distro I have > tried; the dmesg error is the one I sent last time, and the one others have > gotten, about inability of Alsa to read the frequency at ep 01x. The display > reads 96 (kHz) and the device is dead. With pre-2.6.32 kernels the situation > is even worse, but the device does not work. > > USB2.0 mode appears to work perfectly with a recent snapshot of Voyage, > kernel (2.6.38, Alsa 1.0.24, compiled for 2.6.38) no matter what order one > plugs or powers the devices. This is only for two machines, but quite > different architectures: an old VIA C7 mini-itx and a brand-new > Zotac AMD Turion Neo M880G. Some of my inconsistent results in my > last post were due to my being stupid.
> > Voyage-MPD 0.7.0 works most of the time with the DAC in USB2.0 mode, > but not always. Again, if the DAC is plugged in to the running computer > and itself is powered, or if the computer is booted while the DAC > is powered and connected, it is OK, but powering up the computer first > and then the DAC does NOT work; it does with the new snapshot. > > Anyway, it would appear that the newest version works perfectly in USB2 > but nothing works in USB1 mode. However, all USB ports these days > are USB2 (or 3--haven't tried those yet, but I have 2 on the AMD > box) and the DAC plays redbook CD files as well as high-res files > perfectly in USB2 mode, so for me, at least, the case is closed. Just to clarify, USB Audio Class 1 and USB Audio Clsss 2 have nothing to do with whether a USB port is 1.0 or 2.0. The former is the class for USB audio, with USB Audio Class 1 (UAC1) being limited to 24bit/96Khz. USB Audio Class 2 (UAC2) lets one play files of higher resolution than 24bit/96Khz. Yes, you should use a USB 2.0 High Speed port for UAC2 so you can play 24/192 files. So, UAC1 and UAC2 is different from USB 1.0 (full speed) and USB 2.0 (high speed 480 Mbit/s). The switch on the back of the Ayre lets you pick between UAC1 and UAC2. Nick _______________________________________________ Voyage-linux mailing list [email protected] http://list.voyage.hk/mailman/listinfo/voyage-linux
