I am experiencing audio ticks when doing calls from SIP or console to ISDN. Calls. Everything appears fine when doing ISDN->ISDN or SIP->SIP. Console calls results in 5-8 ticks a second, SIP calls are dependent on buffer size - 16ms are 1 tick a second, 8ms are 2-3 ticks a second. I recently moved the ISDN board and software to an upgraded PC with the exact same software configuration - prior to moving the audio was fine. There are no IRQ conflicts, and just for the heck of it I have experimented with moving the card to another PCI slot, enabling/disabling APIC/ACPI in kernel, using version 1.4.0 and trunk software. I have also tried to load and unload the computer using hdparm and other testprograms, it does not affect the ticking or zttest results. zttool reports no IRQ misses. zttest results are normally 99.755 but occasionally (once 2-3 minutes) dips to 99.96 or worse (99.92). - using ztdummy for timing and then running zttest is all bad I have tried to adjust the clocks using adj_clock (in zaptel source) by Cohen Tzafrir (Not knowing exactly what it would improve), it did adjust the clock to 100% with an occasional dip (every 2-3 minutes as before) - but it didn't affect audio ticks, which is always consistently bad. Zaptel is not compiled using MMX support. I would really appreciate any thoughts on this !!! Regards Rasmus