[Freeswitch-users] Meaning of packet loss log message

Hello list, I'm seeing log entries such as this: switch_core_media.c:2509 [VBR]: Correcting calculated ptime value from [40] to [20] to compensate for [1] lost packet(s) They are often accompanied by very audible clicks without any PLC. RTCP does not appear to report related packet loss according to Chrome's webRTC stats. This is between SIP and portaudio. Does anyone know at which stage that packet loss occurs, or what could be causing it? Thanks, Thomas