OOMA.com is not compatible with 3CX. OOMA uses a proprietary technology, incompatible with SIP, which is the protocol used as standard not only by 3CX but also by many VoIP providers and vendors.
Dan,
How do you like ooma? How long have you been using it? I read about it some time ago and when I saw how they were intending to make use of their clients' PSTN lines to route calls, I was alarmed. Are you letting them use your PSTN line? Do you get connected consistently?
Thanks for your feedback.
Halea