Hi, I have a trunk from Gradwell. It is a SIP extension of their voip server. When a call comes in on this trunk, the caller will only hear beep-beep-beep or simply gets disconnected. In the pbxes.org log I see this: May 20 19:16:23 VERBOSE[100594] chan_sip.c: Oooh, format changed to 8 May 20 19:16:24 VERBOSE[100594] chan_sip.c: Hangup call SIP/2028600-df49, SIP callid 25706de614a1696f2dcf1eca@195.74.61.16 What is this format changed to 8 problem and what can I do to avoid it?