[asterisk-users] SIP/Console -> ISDN ticks

Rasmus Erfurt
Wed, 07 Feb 2007 06:08:35 -0000

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