Weird real-time scheduling problem

Hi All,

I have Ubuntu 9.10 and gnuradio 3.2.2 installed on two identical PC
configurations, with two USRP2s (one per PC, obviously).

on both computers I have /etc/security/limits.conf file with the
following line:
@usrp - rtprio 50

and on both of them I set the permissions for usrp2_socket_opener so I
can use USRP2 as a non-root user. On both PCs I run gnuradio sa user
“moment” with following ID:
uid=1000(moment) gid=1000(moment)

However, on one of the PCs I can’t get real time scheduling working. I
get “Warning: failed to enable realtime scheduling” for every example
I tried, although the examples do continue to run.

Any ideas about what could this be? Is there some other thing that has
to be changed to enable real-time scheduling? Could it be that some of
the group/user manipulation files are corrupted?