Hallo!

This is a problem with your soundcard. Make sure your soundcard has 4 channel in and out (and that ALSA supports it). It seems that it hasn't. (ALSA: cannot set channel count to 4 for capture)

My card is a RME Hammerfall. One week ago everything worked fine. Then I compiled PD 0.38 and now it doesn't work anymore (as I mentioned before). I also tried to uninstall and reinstall pd 0.37, but now also with the old 0.37 it doesn't work ... it's really crazy!

You have to tell PD to use jack like this: pd -jack Or set it in the media menu. If the flag doesn't exist or the Media Menu doesn't have a Jack entry then pd is not compiled for JACK --> you have to recompile or install the Debian package, which works out of the box.

I tried all debian package and different configure flags ... :( I also tried to reinstall jack.

Thanks again, LG Georg