I figure out, that there is a problem in pthread - library.

[code]
(gdb) backtrace
#0 0x00092f34 in __pthread_initialize_manager ()
#1 0x00093384 in pthread_create ()
#2 0x000623ac in SDL_SYS_CreateThread (thread=0x277b48, args=0x277e6 at SDL_systhread.c:99
#3 0x00061e34 in SDL_CreateThread (fn=0x1ee990 <SDL_Threads>, data=<value>) at SDL_thread.c:257
#4 0x0005406c in SDL_OpenAudio (desired=0xbffffd10, obtained=0x1eedb4) at SDL_audio.c:500
#5 0x0007d744 in Mix_OpenAudio (frequency=513860, format=28164, nchannels=2321944, chunksize=<value>)
at mixer.c:291
#6 0x000089d8 in main () at fpc4gp2x.dpr:96

What are the next steps? I don't know.

Cheers,
Thomas