This error occurs when the connection from the THETA to the computer is not established.
Look into the connection between these four pieces:
1 Camera => 2 Computer USB Port => 3 UVC Blender = > 4 OBS
If the problem is that you have a video stream, but it is in equirectangular mode (you lack 360 navigation), then the problem is probably between:
3 UVC Blender => 4 OBS => 5 YouTube Streaming Event
Possible problems that cause Status:0x800705AA errors:
camera is not in live streaming mode
Test to make sure you can stream an equirectangular video and display it locally with just OBS, not YouTube. A blue Live light needs to be on.
camera is not plugged into USB port or power is off
The THETA has a user configurable power off period. Maybe your camera turned itself off? The USB connection on the THETA is 2.0, but it will work with a 3.0 port on the computer. Try turning the THETA on in live streaming mode first, then plugging it into the computer
OBS not finding UVC Blender
Despite showing that OBS is connected to UVC Blender in the Device selection, sometimes it is not registering. Select another device such as THETA S streaming in dual fisheye mode to test the connection, then flip back to THETA UVC Blender. Even during a live stream with YouTube, you should be able to change the device. If it's not streaming in equirectangular mode on OBS, it will not stream in 360 navigation on YouTube
Camera firmware needs update
THETA UVC FullHD Blender needs firmware 01.82. If you have an earlier firmware, upgrade using this guide.