There is no "beta" firmware now. The firmware that is being pushed out this week is the "real thing" production firmware. If things go according to plan, you have about 5 weeks before your devices stop working with Google Voice, unless you enable remote provisioning and your devices are properly added to the OBiTALK web portal, so that the new firmware is pushed to your device(s).
Issues with calls forwarding calls to non-OBi devices (i.e. regular telephone numbers) is unrelated to the OBi firmware. You might just have some sort of configuration error, or one or more of your linked forwarding numbers is grabbing the call before the others can do so. You can troubleshoot this via a process of elimination: delete every single linked forwarding number off of your Google Voice configuration on:
https://voice.google.com/settings Then, add back just one linked number, preferably a standard mobile phone number with one of the "big four" mobile carriers, and enable conditional call forwarding on that mobile number to send busy or unanswered calls back to your Google Voice number. Have some callers try calling your GV number, and see what happens. If every call is successfully forwarded to your mobile number, and CCF is successfully sending unanswered or busy calls back to your GV voicemail, then move on to adding one more linked number, lather, rinse and repeat.
