mplayer slowness and kernel

[Jan Willem Stumpel <jstumpel@planet.nl>]

With the 2.6.29 kernel (from the linux-image-2.6.29-2-686
package), playing a movie with mplayer uses up to 95% cpu. mplayer
becomes very slow and jerky, with "stuttering" sound, and "Your
system is TOO SLOW" warnings. No twiddling of mplayer's parameters
helps.

When I go back to the slightly older 2.6.26 kernel
(linux-image-2.6.26-2-686), mplayer works properly again (about
20% cpu usage and no warnings or "stuttering", even at full screen
size.

Is this a known problem?

Regards, Jan