Has anyone got a recommended configuration for setting up iTalk VOIP on a LinkSys SPA2102?  And ideally in combination with a Dynalink RTA1025W router?

When I first installed all this, it ran fine.  But for some reason the voice quality started getting bad.  I have tried reinstalling from scratch and have updated firmware, but no change.   I also tried some of the configuration parameters provided by 2Talk (see http://www.2talk.com/2102.html), but no luck.  I was hoping that someone has some configuration instructions for iTalk.  Unfortunately Slingshot doesn't provide these.