I too started getting this, have only tried Overwatch since noticing.
0.16.2
Same exact symptoms as described above.
OBS UI is still responsive, but the canvas freezes (game capture and camera).
Here's a snippet of my log, showing the freeze in under two minutes of having gone live.
23:42:30.654: User switched to scene 'Cam Only'
23:42:32.530: User switched to scene 'Game!'
23:44:01.991: device_texture_create (D3D11): Failed to create 2D texture (887A0005)
23:44:02.358: device_texture_create (D3D11): Failed to create 2D texture (887A0005)
23:44:02.394: device_texture_create (D3D11): Failed to create 2D texture (887A0005)
23:44:02.458: device_texture_create (D3D11): Failed to create 2D texture (887A0005)
23:44:02.491: device_texture_create (D3D11): Failed to create 2D texture (887A0005)
23:44:03.125: device_texture_create (D3D11): Failed to create 2D texture (887A0005)
23:44:03.158: device_texture_create (D3D11): Failed to create 2D texture (887A0005)
23:44:03.191: device_texture_create (D3D11): Failed to create 2D texture (887A0005)