I use stock phone with gv call back to make a outbound internet phone call. Also I can not finish skype test call either.
Seems like something between 3.2 and 3.3 has broken things for CSipSimple.
On 3.2 this app worked fine, able to make and receive calls.
On 3.3 the app registers with the SIP provider ok and can initiate and also receive calls. However when the call is answered, there is no audio from the phone to the remote end. Audio from the remote to the phone is ok. When you hang up the call, you get a message: "Unfortunately, CSipSimple has stopped".
I have re-installed the app to be sure that isn't the problem. The broken outbound audio also isn't due to a firewall problem (which is often the cause of that problem). I have tested between several phones that have no firewall between them.