In a previous message a user is recommended to compile a driver to use
snd-usb-asyncaudio should be available on the last version for the RP2.
The snd-usb-asyncaudio driver has been merged in the mainline linux kernel since version 3.11 with the name snd-usb-hiface.
For kernels >= 3.11 just use the mainline driver and report issues to the alsa-devel mailing list.
This repository will be kept on-line in case someone needed the driver on older kernels, and to document the out of tree development history.
Please check or post your debug data.