Well, as far as I am aware there is nothing that comes close to the OBi110, and nothing with IPv6 support.
I know you said:
Arek wrote:Don't had a time for full diagnose. And to be honest don't want to change settings on my router as they are perfect for me now.
But you may have no alternative. If it's your router preventing registration then buying another IPv4 telephone adapter won't help. IPv6 would eliminate any NAT traversal problem
, but as I pointed out above, there doesn't appear to be an OBi110 equivalent that supports IPv6.
Arek wrote:Ideal will be something similar to that one I have now, but I can consider VOIP phone if I have to.
There are a few IP telephones out there that have a FXO Line port, but again, none that have IPv6 support out of the box.
Obihai offer the OBi1022, OBi1032 and OBi1062 IP phones which apparently are upgradeable to IPv6 and these can be used with their OBiLINE adapter. Unfortunately though, at present IPv6 doesn't appear to be enabled on these phones, I should also point out that when using an OBiLINE adapter with the OBi2xx series people have complained about an echo on most PSTN calls. Even if they had IPv6 enabled and the OBiLINE adapter worked as it should Obihai don't appear to be selling these in the UK anymore.
Your router should have an option to backup your current configuration. This would allow you to alter various settings in order to try and get your OBi110 online. Should anything go wrong, simply restore your router.