I'm curious, what have you needed to change in the
kernel?
I'm on gentoo-sources 2.6.11-r9 and it's been fine.
I've been running a vanilla 2.6.10 (no genkernel) with the
RT-LSM module loaded which was absolutely OK for my needs
(~16msecs latency on my cheap USB soundcard).
Unfortunately, I trashed this kernel when playing with some
webcams, so I currently run a 2.6.12 without any patches, but
I should build a realtime 2.6.12.
Unfortunately, I'm not that familiar with kernel building, and
since the RT-LSM module got dropped I'm in need on some info
how to build a 2.6.12 for audio work before I can continue
kernel exploring ;-) .
Best regards
ce