For those looking for high bit rate, non-usb, stable multi-channel input
and output on the pi (6 in 8 out), this current Kickstarter may be of
interest. I'm not affiliated with the guy responsible for this , but I do
have his first board, the 2 in 2 out version. So far it seems very stable
at reasonably low latency settings in JACK and has the added benefit of
mainline kernel support. If the multi-channel version works nearly as well
it may be a winner.
https://www.kickstarter.com/projects/1250664710/audio-injector-octo-surroun…