After setting up ubuntustudio (7.04) with a real-time kernel (2.6.20-16-realtime), I was experiencing DIO errors every few seconds.  Exploring this taught me alot about how to set priorities on a real-time kernel, mainly with the command 'chrt'.  However, I don't think it is meant to be used directly on an application, since there might be parts of the application that are not supposed to run in real-time at a high priority.  
<br><br>Nonetheless, running:<br>r@pal:/etc/sysconfig$ pidof pd<br>12079<br>r@pal:/etc/sysconfig$ chrt -p 60 12079<br><br>sets pd running as:<br>r@pal:/etc/sysconfig$ chrt -p 12079<br>pid 12079&#39;s current scheduling policy: SCHED_RR
<br>pid 12079&#39;s current scheduling priority: 60<br><br>and the xruns go away.&nbsp; I don&#39;t know too much about the different threads pd is running on, but I was under the impression that pd is supposed to start in real-time with a high priority.&nbsp; Yet, due to the apperant changes from chrt, I would think that it was not running in real-time.&nbsp; I&#39;ve tried this on versions 
0.40-3 and 0.41-7, and real-time scheduling is not specifically turned off in the pd start-up settings.&nbsp; <br><br>Any thoughts?<br><br>regards,<br>rich<br>