Hi Arek - welcome to the forum.
There's a few possible problems here:
Check the format that your VOIP service provider requires you to dial. Some require the number in full international format.
Your router may be blocking the ports required for speech (RTP). Recommended ports to open for the OBi110 are:
TCP Ports: 6800, 5222, 5223
UDP Ports: 5060 to 5063, 10000 to 11000, 16600 to 16998, 19305
An easy way to test for this problem is to temporarily put the local ip address of the OBi110 in your router's DMZ. This will open all ports just for testing.
If SIP calls incoming to you are working ok, then there should be no issue regarding compatibility of CODECs.
Your digit maps will not prevent the call being correctly routed, but may be making it very slow to connect – more than ten seconds. If international format is required then something like this may be good for you:
Service Providers -> ITSP Profile A -> General -> DigitMap:
(0048xxxxxxxxx|xx.)
If the nine-digit format is correct, then something like this may work well for you:
Service Providers -> ITSP Profile A -> General -> DigitMap:
(xxxxxxxxxS3|xx.)
We can fine tune the digit maps if you let us know exactly what digits you need to dial.