[Asterisk-Users] Are my expectations too high?

[Dr. Michael J. Chudobiak]

> I'm getting a slight echo...sometimes...it varies from call-to-call,
> but the biggest problem I have is a constant hiss in the background.
> Again, this varies from call-to-call.  I know my SIP phones are fine
> as SIP-to-SIP calls on my LAN work perfectly.  I only have problems
> going out to the PSTN.


Get an FXO card with hardware echo cancellation. I use the Sangoma 
A20002D (four FXO ports with echo cancellation). It definitely costs 
more, but the hardware echo cancellation makes a huge difference in call 
quality! Software echo cancellation doesn't really work...

I don't know what to suggest about your hiss problem though.

- Mike