Hey again, and sorry for the double emails, but I'm having another (separate) issue Intermittently during call setup PJSIP is failing to send any SRTP data, constantly failing with this message: Error sending RTP: replay check failed (index too old) There doesn't seem to be any consistency to when or why this happens. My only current assumption is that it's based off whatever number is picked as the initial sequence number (because it seems random), but I have no idea. Any theories on this? Best, Colin