On Wed, Jan 31, 2018 at 11:29 AM, Christian Affolter <c.affolter@purplehaze.ch> wrote:

Yes, it's a proprietary driver and I don't have access to the source
code. I could contact the vendor and ask if they observed the same or a
similar issue already.
However, I'm wondering what arecord and jackd-dummy/alsa_in are doing
different compared to jackd-alsa.

Sorry if this is not relevant (I'm not quite following what's happening), but could

it be that the difference can be explained by different alsa paremeters set

by arecord and jack? Have you tried to run "arecord -L" and find the most

low-level device to record from (which jack probably uses).

For instance by running something like "arecord -D iec958:CARD=M2496,DEV=0"

(my soundcard).

If that is the case, then it's probably the default alsa device that does something magic

when accessing a more low-level device.