Daniel:
I'm testing an early sample of the Wavelength Wavelink, a USB to S/PDIF adapter that supports 44.1-192 KHz sample rates and uses async usb to talk to ALSA. It works and plays all of the sample rates correctly with the git version of Alsa from 7/30/2010 whenthe files are sourced from the network. However if I try to play from a usb source to the usb dac it doesn't work and the whole system gets unstable. The platforms I have tested it on seem to have a single USB host interface but with USB 2 there should be enough bandwidth to pass the data from a USB stick to the cpu and back. If I use an older 96 only usb dac on the same system it works (unless the down conversion isn't a direct divide, which overloads the CPU, but that is a different issue). The problem seems to be sample rate independent and hits the moment I try to access the file. This is using MPD as a player.
What additional info do you need to troubleshoot this? Is it an intrinsic limitation to the interface? What additional tests should I do? It's possible it's a hardware issue but how do I divide them so I can go back to the hardware guy if it's his issue?
Demian Martin
Product Design Services