[PlanetCCRMA] 2.10 Kernel and lsm on FC2

[Crispin]

Well, I've made the leap from RH9 to FC2, but seem to have twisted both 
ankles on landing :(

1. I run muse, and all is fine at first, but after a few minutes of 
operation, about 50 xruns occur at once.

Can anyone help with this?  The kernel is 2.6.10-0.2.rdt.rhfc2.ccrma, 
soundcard is an sblive. 
chkconfig shows that rtload is indeed turned on. 
jackstart complains that:
   jackstart: cannot get realtime capabilities, current capabilities are:
       =ep cap_setpcap-ep
    probably running under a kernel with capabilities disabled,
    a suitable kernel would have printed something like "=eip"
But I understand from the list archives that it's actually working 
anyway.  Is this true and how can I check?
I have set jackstart, qjackctl and muse to be suid root (just to be sure). 
automount is also off, and the windowmanager is windowmaker.

2. I cannot load the snd-serialmidi module.  Apparently it contains 
unknown symbols, specifically
snd-hidden-kcalloc
snd-hidden-kcfree
snd-verbose-printk

Any suggestions on either of these topics would be much appreciated!

Thanks in advance,

Crispin