hello,
I just install raspbian release and update it. then install pd 0.44.1 (without any specific optimisation flag)
I made the standard optimisation :
in /etc/security/limits.conf
and dwc_otg.speed=1 in /boot/cmdline.txt as suggested by miller
I use a uca222 beringher (that cost about 20 or 25€) sound card. trying the test audio and midi, there is no click with 10ms audio buffer (with adc~ enable).
this is with usb keyboard / mouse combo plugged and graphical interface (for the system and for pd).
without X, audiobuf can be as low as 5ms
having a usb keyboard did not change anything for me.
i'm very happy
cheers c