[PD] /dev/dsp newbie problemo

[roc]

hi list
after a while pding on OSX i'm trying to switch to linux.
compilation was ok, but when i start pd i get:

	/dev/dsp (writeonly): Device or resource busy
	/dev/dsp (readonly): No such device or address
	error: failed to open MIDI ports; continuing without MIDI.
	audio I/O stuck... closing audio and MIDI

i don't care about the MIDI part, cos i won't be using any, but i 
obviously want some audio ;~)
i assume it might be something very easy to solve, but i'm still a 
newbie here and i get lost with dev permissions etc.
hints?
r