The latest firmware that became available in June/July 2017 is version 4.0. The one before that was in Nov/Dec’16 and that was version 2.0. There was no version 3.0 released.
As far as I know, only iOS 9.5 (or is it 9.6?) and later can stream direct to the OPN. MacOS does not have the BLE protocol and therefore cannot stream directly to the OPN.
I use Skype on my Windows laptop for business calls using my OPN all the time. I just use my Plantronics Voyager Focus headset like usual for Skype. I wear my OPN inside of my ear (like in ) then I put my headset on my ear on top of the OPN. If you have a larger headset that goes over your ear (instead of just on top of your ear), then you can wear your OPN normally behind the ear and it would work just fine, too. Hopefully by the end of this year Oticon will come out with the ConnectClip 3.0 streamer and this will solve your problem with regular Bluetooth devices.
For watching video on your computer or your TV (where you don’t need a mic function to talk back), just connect your computer or TV into the Oticon TV Adapter 3.0 and you’ll get direct streaming into the OPN.
The current version of Bluetooth only supports a subset of BLE for control commands and not for full audio data transfer. BLE 5.0 (recently released as a standard) will support full audio data transfer, but the device mfgs have to support it first, then the HA mfgs have to support it next. That may be a few more years out.
You can’t really tell what firmware you’re running unless your OPN is hooked up to Genie 2. One way to guess is that if you have lots of connection and streaming issues between your OPN and the iPhone, and/or your OPN reboots randomly frequently, then most likely you’re still on the old firmware version 2.0. The newer firmware version 4.0 should be a lot more stable with very few random reboots and less connection and streaming issues between your OPN and the iPhone. When iOS 11 comes out in a couple of months, the remaining connection and streaming issues (if any) should go away for the most part.
In firmware 2.0, if calls don’t get through to the HAs, it’s probably because the HAs got disconnected from the iPhone randomly. This issue should go away after you update to firmware 4.0 on the OPN and to iOS 11 on your iPhone.