I'm wondering if anyone else is having an issue with the native SIP client since they received the 5.1 update a few days ago?
I've been using the native SIP client in my HTC One M9 for a few months without issue, but since the update I cannot make outgoing calls. Incoming work normally.
If I use an app like Zipper all works well so I'm guessing the issue is an Android software problem.
Any advice welcome.