Hi everybody, as a result of an outage of my usual VoIP provider I opened an account at an other provider. And there to my great surprise, everything worked marvellous. That revitalized my interest in the strange error of the SPA3102 that I had already abandoned weeks ago. And led me to a profound debugging session, which eventually brought no solution for me but showed me at least what caused the problem in the first place. The crucial point is that the ATA proposes and accepts depending on your configuration different codecs during the SIP-negotiations (INVITE). In my case for instance it looked like that: a=rtpmap:0 PCMU/8000 a=rtpmap:2 G726-32/8000 a=rtpmap:4 G723/8000 a=rtpmap:8 PCMA/8000 a=rtpmap:18 G729a/8000 a=rtpmap:96 G726-40/8000 a=rtpmap:97 G726-24/8000 a=rtpmap:98 G726-16/8000 a=rtpmap:100 NSE/8000 a=rtpmap:101 telephone-event/8000 After making a call via PTSN the same offer during the attempt to call out via Line1 had melted down to a=rtpmap:0 PCMU/8000 a=rtpmap:100 NSE/8000 a=rtpmap:101 telephone-event/8000 As the server of my original provider accepted only PCMA bad luck, the second accepted PCMU so no problem occurred. Curiously in the same state (without reboot) the SPA3102 had no problem in the case of a call from outside (Line1 and PSTN) to accept PCMA. Unfortunately I could not convince the device through any changes in the configuration like “Preferred Codec” or “Use Pref Codec Only” to change that behaviour. So I came to the result, that there has to be a nasty bug in the firmware which will be hopefully addressed very soon. Regards Peter ... View more

Hi Patrick, Thank-you very much for your answer. As I changed in the same time the wireless phone which stood next to the SPA3102, I mistook the ringing of the basestation of the DECT-phone for bell of the SPA3102. But luckily your answer pointed in the right direction and the case could be solved easily. Regards, Peter ... View more