The security alarm check-mark can be easily removed. I don't know why you didn't try that first. However, this might be caused by the firmware version on your device, which is in the process of being updated to support Google Voice's new interconnection to OBi products.
Pick up the phone attached to the OBi. Key in ***0 then 1# and write down the version it reads back to you, and post it here.
By the way, do not use the security alarm feature on OBiTALK. It kills the ability to use the OBi for regular calling, and I don't know if it is, or will be, compatible with the new firmware. Contact your alarm monitoring service to upgrade to a direct IP connection and/or a 4G radio communicator. Connecting alarm panels via dial-up phone lines is old technology, and trying to make it work with a VoIP ATA is asking for trouble.
Alarm Panel--->IP gateway-->your ISP-->Internet-->alarm monitoring center
|--->4G radio----->alarm monitoring centyer