On Sun, Mar 27, 2011 at 2:20 PM, Peder Hedlund wrote:
More importantly, you can only use two sound cards with JACK at the
same time if their sample clocks are synchronized. This can be
achieved with an S/PDIF connection between the two cards, but of
course that's only an option if both cards actually have digital
Without synchronization the sound cards' sample clocks will drift,
which invariably leads to xruns. This is not JACK's fault by the way,
it's simply how the hardware works.
The only other solution to this is resampling, which is what alsa_in
and alsa_out do. But resampling will have some negative effect on
audio quality, so I would only use it as a last resort. Why exactly
don't you want to use the USB device for both capture and playback?
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