We have an Epygi Quadro2x configured with 8 Linksys SPA-941 IP Phones.

often while on a call, the inbound audio will cut out for up to 10
seconds. The remote party can still hear us, but at our end it sounds
like the line has gone dead. After 10 seconds (or sometimes less) the
inbound sound resumes.

All our phones, all quadro extensions,
and our ITSP providers are configured to use G729a as the preferred
codec. I've also tried disabling silence suppression on the G729a
protocol (under RTP settings) but this seems to have made no difference.

The Quadro is connected directly to our internet connection (bridged mode) so I don't believe the issue is to do with NAT.

anyone have any ideas what could be causing this issue? I figure there
are a number of places the problem could be occuring, either somewhere
between our IP phones and the Quadro (internal network), or between the
Quadro and our ITSPs.

Any help would be greatly appreciated.