non meaningful output with pthread

Hi, I'm doing a sequencer and since I'm doing optical feedbacks I
experience bad crashes. The engine becomes unreliable and gdb gives
useless output.

I'm doing everything in view of thread safety from atomic operations to
mutices, syncing ...

please take a look at http://ags.sf.net


[New Thread 0x7fffb8db1700 (LWP 917)]
[New Thread 0x7fffb85b0700 (LWP 918)]
** Message: short write, write 88 frames
[New Thread 0x7fffb7daf700 (LWP 919)]
** Message: short write, write 240 frames
[New Thread 0x7fffb75ae700 (LWP 920)]
** Message: short write, write 120 frames
[New Thread 0x7fffb6dad700 (LWP 921)]
** Message: short write, write 521 frames
[New Thread 0x7fffb65ac700 (LWP 922)]
** Message: short write, write 279 frames
[New Thread 0x7fffb5dab700 (LWP 923)]
[New Thread 0x7fffb55aa700 (LWP 924)]
** Message: short write, write 176 frames
[New Thread 0x7fffb4da9700 (LWP 925)]
** Message: short write, write 160 frames
[New Thread 0x7fffb45a8700 (LWP 926)]
** Message: short write, write 240 frames
[Thread 0x7fffe3776700 (LWP 883) exited]
** Message: short write, write 400 frames
[Thread 0x7fffb95b2700 (LWP 916) exited]
[New Thread 0x7fffb3da7700 (LWP 927)]
** Message: short write, write 120 frames
[Thread 0x7fffe0770700 (LWP 889) exited]
** Message: short write, write 80 frames
** Message: short write, write 160 frames
[Thread 0x7fffb5dab700 (LWP 923) exited]
[Thread 0x7fffb6dad700 (LWP 921) exited]
** Message: short write, write 80 frames
** Message: short write, write 80 frames

...

Couldn't get registers: Kein passender Prozess gefunden.
(gdb) bt
#0  0x00007ffff3a42cef in start_thread (arg=<optimized out>) at
pthread_create.c:349
#1  0x00007ffff378ce6d in clone ()
at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#2  0x0000000000000000 in ?? ()