With the proxies redundantly set to the provider's SIP-server, it has been running for over a week without problems now, including the weekend. Unless O2 fixed something with their servers, this...

An owner of the tp-link TD-W9960v (not offering the possibility to set a proxy for the SIP connection), who has O2 as provider and is experiencing the same issues, reports the following (impractical)...

@David-TP I'm afraid my attempts to communicate with Abner Zeng, the senior engineer, have failed. Both replying or sending the mail to the TP-link e-mail address that he provided, bounce. What I...

@David-TP I might have found a solution, but I'm not sure. It could be just a glitch. Under “SIP Proxy” and “Outbound Proxy” I added the SIP address from O2 redundantly. Before, it was left empty...

@David-TP Just sent you the new log, as it didn't take a day before dialing out stopped working again.

The BETA is up and running. So far without issues. Debug is turned on in SysLog. I'll let you know, if something happens or when it manages to withstand the weekend this time.