[vdr] VDR 1.3.15 gets unusable slow after a short time

[post <post@mhr.at>]

I have no idea, what is going on here. This is my system:

development-sources-2.6.8.1 (also tried 2.6.9 and 2.6.10_rc1) / Gentoo Linux
- selected special kernel options:
- use register arguments
- message signaled interrupts (MSI and MSI-X)
- use 4kb for kernel stacks instead of 8 kb

dvb-kernel that comes with kernel sources (also tried actual CVS)
NPTL enabled
glibc-2.3.4.20040808-r1
gcc-3.3.4-r1
one Hauppauge WinTV Nexus-S + CI-Slot-Adapter 545
one TechniSat SkyStar2 (also uses stv0299)
one Hauppauge WinTV analog-card

Until now, I only installed vdr 1.3.15 (with a selfadapted vdr-1.3.14-r3 
ebuild from gentoo.de) with the remote-plugin.

When I start vdr, everything seems to be working fine. No abnormal messages 
in /var/log/messages and no errors.

After some time has passed, vdr seems to go to sleep. It still gives the 
live-signal on the FF output, but it does not react on remote-keypresses. 
In that state vdr is still running, and absolutely no error messages or 
abnormalities in /var/log/messages.

I just did the test: Pressing the MENU button, and waiting. Nothing 
happens, looks like a complete ignore, live-signal still running on the FF 
output. Finally the menu-screen comes up, about 5 MINUTES after the menu 
key was pressed.

What could be the problem?

After a restart of vdr everything seems to be normal, but then suddently 
that behaviour kicks in without further notice. All the rest on that 
machine is running normally, I also have xorg-x11 + kde 3.3.1 installed, 
and actually I am watching the live-signal on my monitor using kvdr.

--
Sincerely,
Master One