My (Ooma Sent Yealink T48S) never worked out of box. I got sent to level 3 support which wanted me to go into my Yealink T48S web config. The webconfig was broke, so we could never get into it. After several tests we realized it was the phone and not my network. They decided to just send me a new phone.
However, I TFTP flashed it to an older version than the stock ooma one sent. I can now access the webconfig of the phone, however, I don’t have the Ooma provisioning server URL. I believe the phone will probably update and work if I can get that.
It seems weird to me that some providers like ring central are so open with this sort of information… shrugs