For the past couple of years I have been using several SPA942 IP phones, one SPA9000 IP PBX, and one SPA400 gateway.
The system works fine, but I've never been too pleased with the voice quality when calling to/from the PSTN. SPA942 to SPA942 calls sound better, as do SPA942 to FSX extension calls. The SPA400 is currently configured for G7.11u codec preferred, 30ms packetization, and VAD off, but I have experimented with other settings too.
I'm wondering if the SPA8800 would provide improved PSTN voice quality over the SPA400?
Do any configuration guides exist to describe SPA8800 / SPA9000 integration as there exists for SPA8800 and Asterisk?