OK, thanks.
Not to derail your thread, but to further clarify the "early media" issue: Big picture: GV, itself, is designed to be the one inbound call handler/manager, and thus, it is not designed to interact nor to otherwise be compatible with any subsequent call handling technology. GV, itself, is using early media on inbound calls to your GV number: when you enable GV call screening, for example, the caller hears ringback tones, while GV forwards the call to the forwarding number. At that point, when you "answer" the forwarding phone, the call is still in the early media period, and the person answering will hear Kiki tell them to press "1" to accept the call or press "2" to send it to VM. Only after that happens, or 25 seconds expires, is the call actually answered (meaning, the VoIP equivalent of "answer supervision" is sent, and the parties are connected).
This same early media behavior is occurring on every inbound call to a GV number, while GV forwards the call to all the forwarding targets (forwarding phones, Chat and/or Hangouts). Thus, GV, by design, intentionally ignores subsequent early media behavior on the called number, as there would be no way to interact with it from the calling party's end. This is the same reason why various inbound services, like human answering service bureaus, or certain TFN IVR systems, are incompatible as forwarding destinations for a GV number.
Bottom line: some OBi users think of GV as a free inbound VoIP trunk, like a SIP VoIP DID. It's not. It's a call forwarding and call management system, and it's intended to be used in that manner with forwarding phone numbers that don't do further call processing.