Kdenlive freezes when playing something

Hi,
today I've installed a fresh version of ubuntu 9.10 on my desktop PC. After installing graphic drivers I started Kdenlive.
After I've added some pictures, I played the arrangement, but after a few seconds it stops and the window was greying. Only thing to do then was killing the process.
I changed some settings, like switched to ALSA but nothing worked.
I have the same issue with videos, that I played. Kdenlive is not even working on my notebook. Any suggests?

Crash report:

Application: Kdenlive (kdenlive), signal: Segmentation fault
[KCrash Handler]
#6 0xb310fff7 in ?? () from /usr/lib/libSDL-1.2.so.0
#7 0xb31107ac in ?? () from /usr/lib/libSDL-1.2.so.0
#8 0xb30fdd84 in SDL_SetVideoMode () from /usr/lib/libSDL-1.2.so.0
#9 0xb316e3e4 in ?? () from /usr/lib/mlt/libmltsdl.so
#10 0xb7893983 in mlt_consumer_start () from /usr/lib/libmlt.so.1
#11 0xb316d924 in ?? () from /usr/lib/mlt/libmltsdl.so
#12 0xb7893983 in mlt_consumer_start () from /usr/lib/libmlt.so.1
#13 0xb786a685 in Mlt::Consumer::start() () from /usr/lib/libmlt++.so.2
#14 0x080cc52c in _start ()

Developer Report

Application: Kdenlive (kdenlive), signal: Segmentation fault
[Current thread is 1 (Thread 0xb53fe700 (LWP 7092))]

Thread 6 (Thread 0xb02f3b70 (LWP 7173)):
#0 0xb781b430 in __kernel_vsyscall ()
#1 0xb5ded94d in pthread_join () from /lib/tls/i686/cmov/libpthread.so.0
#2 0xb48272a8 in ?? () from /usr/lib/mlt/libmltsdl.so
#3 0xb77f8fe4 in mlt_consumer_stop () from /usr/lib/libmlt.so.1
#4 0xb4829a9a in ?? () from /usr/lib/mlt/libmltsdl.so
#5 0xb5dec80e in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#6 0xb5ed17ee in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 5 (Thread 0xad0b7b70 (LWP 7184)):
#0 0xb781b430 in __kernel_vsyscall ()
#1 0xb5ded94d in pthread_join () from /lib/tls/i686/cmov/libpthread.so.0
#2 0xb4828de9 in ?? () from /usr/lib/mlt/libmltsdl.so
#3 0xb5dec80e in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#4 0xb5ed17ee in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 4 (Thread 0xac8b6b70 (LWP 7185)):
#0 0xb781b430 in __kernel_vsyscall ()
#1 0xb5df0e15 in pthread_cond_wait@@GLIBC_2.3.2 () from /lib/tls/i686/cmov/libpthread.so.0
#2 0xb5ede78d in pthread_cond_wait () from /lib/tls/i686/cmov/libc.so.6
#3 0xb77fa548 in ?? () from /usr/lib/libmlt.so.1
#4 0xb5dec80e in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#5 0xb5ed17ee in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 3 (Thread 0xabf33b70 (LWP 7186)):
#0 0xb781b430 in __kernel_vsyscall ()
#1 0xb5ec3ba6 in poll () from /lib/tls/i686/cmov/libc.so.6
#2 0xafae1cc2 in ?? () from /usr/lib/libpulse.so.0
#3 0xafacee09 in pa_mainloop_poll () from /usr/lib/libpulse.so.0
#4 0xafad0c23 in pa_mainloop_iterate () from /usr/lib/libpulse.so.0
#5 0xafad0cf4 in pa_mainloop_run () from /usr/lib/libpulse.so.0
#6 0xafae1bc3 in ?? () from /usr/lib/libpulse.so.0
#7 0xafaa4ac2 in ?? () from /usr/lib/libpulsecommon-0.9.19.so
#8 0xb5dec80e in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#9 0xb5ed17ee in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 2 (Thread 0xab1c0b70 (LWP 7188)):
[KCrash Handler]
#6 0xb3398b9a in SDL_FillRect () from /usr/lib/libSDL-1.2.so.0
#7 0xb48285b2 in ?? () from /usr/lib/mlt/libmltsdl.so
#8 0xb5dec80e in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
#9 0xb5ed17ee in clone () from /lib/tls/i686/cmov/libc.so.6

Thread 1 (Thread 0xb53fe700 (LWP 7092)):
#0 0xb781b430 in __kernel_vsyscall ()
#1 0xb5ded94d in pthread_join () from /lib/tls/i686/cmov/libpthread.so.0
#2 0xb4829395 in ?? () from /usr/lib/mlt/libmltsdl.so
#3 0xb77f8fe4 in mlt_consumer_stop () from /usr/lib/libmlt.so.1
#4 0xb77d0625 in Mlt::Consumer::stop() () from /usr/lib/libmlt++.so.2
#5 0x080cd7b7 in _start ()

Kind regards