[PD] tried but couldn't sync A/D/A

[aishen]

Hi,
When I start pd-extended I got this message : "tried but couldn't sync 
A/D/A" I don't know what it means ?
After googling I didn't find an answer to this question. I have sound in 
alsa, I don't want to use jack because it can't run on my ubuntu 12.04 
(I guess it's because I can't configure it properly)
Is this message important ?
If yes : How can i get read of it ?
kind regards
Henri