Dattani98,

Thanks for the tip. I tried that with my Linksys router. I set up the ports as described but still it does not work (no sound on incoming calls, but outgoing calls work fine). In fact when the Linksys had no port forwarding settings at all, it worked the same.

However, if that is the case that port forwarding is required it renders this service more or less useless: That's because you can not use it anywhere else than at your home... Most cases I'd use this service is "on the go"...