[Asterisk-Users] Re: echo cancellation: the never-ending quest fortruth

[Stephen R. Besch]

Robert Rozman wrote:

> Hi,
> 
> is there any list of problematic motherboards ?
> 
> How does Asus P4P800 behave in this manner or Asus boards in general ?
> 
> 
Robert,

In my experience it's not so much the motherboard as it is the 
interaction of the motherboard with the hardware. The problem is that 
some motherboards make it hard to control things like interrupt 
priority. Many have recommended that you dedicate a more or less 
stripped down server to Asterisk, that is, keep the hardware at a 
minimum. Use as much RAM as practical and the fastest CPU that your 
budget can afford.  Then put the telephony hardware on the interrupt 
with the highest priority (you may have some trouble finding out which 
interrupts have the highest priority). This shortens interrupt latency 
and keeps echo delays as constant as possible (interrupt latency is 
added to the echo path). All echo cancellers work best if the echo delay 
is as constant as possible. Unfortunately, a lot is just trial and 
error, but it really helps to scour the WIKI for information on echo 
cancellation.

Stephen Besch