Ack (Acknowledgement Timeout) on Soft phone - call lasts 30 seconds
 

When I make a call from my Voxalot account, registered via a Grandstream BT102 ip phone to a Draytel Account or Voiptalk running on a softphone (under Windows), the call connection lasts 30 seconds or so, and dies. This happens both with an SJ-Softphone, or with X-Lite receiving the call.

The SJ softphone displays a message :
Awaiting acknowledgement [ 00:xx...
After 30 seconds (actually 31-32 seconds), the call is disconnected and the SJ Phone displays a message in a pop-up.
[ACK Timeout]

I believe the same thing happens in X-Lite but no message is displayed.
A log of this period is attached.

Can any body suggest what is wrong or what I might be able to change to improve this ?

Any suggestions are greatly appreciated. Thanks

I had the same problem, although with a different registration. My problem was my router and NAT -- I ended up just putting my ATA device on the outside of the router and it worked fine after that... Good luck!