for anyone else having probelms I think I have cracked it!!! I was so close to giving up in this.
I just received the below Obdlink LX and rather than hang when pairing, it has a pairing button to click first and then it connected right away!
OBDLink LX 427201 ScanTool Bluetooth: Professional OBD-II Scan Tool for Android & Windows, Green https://www.amazon.co.uk/dp/B00H9S71LW/ref=cm_sw_r_cp_api_i_C4SvDbHX48SVC
I just did a few seconds test recording and the data is all there!
When opening in virb edit it opened the video with all the obd overlays there already!
I tried loads of cheaper ones and when connecting to the virb would just run and run, but if I clicked cancel they would show as connected, but never any data was recorded. These did not work for me:
OBD II Engine Management Diagnostics and Tools on your phone,obd 2, ELM327 bluetooth connection https://www.amazon.co.uk/dp/B075SYF3NH/ref=cm_sw_r_cp_api_i_87SvDb5TD2TYY
ACITMEX OBD2 Bluetooth Scanner, Bluetooth 4.0 Auto OBDII Car Code Reader Diagnostic Scan Tool Upgrade 1.5 OBD II Engine Scanner Fault Code Reader Support IOS,Android,Windows,Hot Plug In Design https://www.amazon.co.uk/dp/B07FYXLRX1/ref=cm_sw_r_cp_api_i_p8SvDbEERP7T0
Torque Pro Elm 327 [ Android ONLY [ V1.5 ] OBDII OBD 2 Bluetooth Fault Code Reader - Track Recorder Camera Accessory https://www.amazon.co.uk/dp/B01AC7I7BO/ref=cm_sw_r_cp_api_i_E8SvDbFH21GF3