[Jack-Devel] what could cause: "impossible sample width (1) discovered!"

Hi All,

i am developing an open source usb soundcard
wich uses standard device class usb drivers.
(I use the LUFA Library and an avr microcontroller)
I got it somehow working, but i can't use all of its
features in jack. It works with the alsa driver in
audacity - i can record and play back sound.
When trying to start jack it works only when i configure
my card to only use the outputs. If i add inputs
or use inputs only i get this error message:
"impossible sample width (1) discovered!"

Does anybody have an idea what can cause
this error? What exactly means width? Is it
maybe an uncorrect samplerate in my hardware?
When starting jack, does jack provide the masterclock
for playback and record? Is it necessary that my
soundcard acts as a samplerate slave or is it
possible to use it as the mastersamplingclock?
At the moment the samples are sent to the LUFA's
part of code by my part of code and hardware at exactly
48kHz sampling clock, which is derived from a
12.288 MHz crystal clock oscillator on my board.

greetings
Felix

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