My problem is solved, though I dont know exactly what it was. Latency did not matter.
What mattered is that I recompiled Kernel without APIC support.
When system boots it no longer writes message "Spurious Interrupt 8259A interrupt 7" (It did before)
It is a message generated in a kernel source named /arch/i386/kernel/i8259.c.
It generally should indicate HW error or something. But it hangs my machine when I am using BTTV and this spurious interrupt message happens.
I removed APIC support, no "spurious interrupt" message anymore, and now it doesnt hang at all! (Although this message indicates HW problem, it still does no problem for my pc)
thank u all,