libobs initialization problem

[Vadim Moskvin]

Hi. I've tried create own UI over libobs, but have problem. My app is .net app, so I wrapped libobs by my .net wrapper library.
I follow instructions from https://obsproject.com/docs/frontends.html#initialization-and-shutdown, but when I use obs_reset_video() I got:
Initializing D3D11...
Available Video Adapters:
Adapter 0: Radeon (TM) RX 480 Graphics
Dedicated VRAM: 4273434624
Shared VRAM: 4265650176
PCI ID: 1002:67df
Driver Version: 30.0.0.0
output 0: pos={0, 0}, size={2560, 1080}, attached=true, refresh=75, name=LG ULTRAWIDE
Loading up D3D11 on adapter Radeon (TM) RX 480 Graphics (0)
D3D11 loaded successfully, feature level used: b000
DXGI increase maximum frame latency success
set_priority: Failed to set process priority class: -1073741790
D3D11 GPU priority setup failed (not admin?)
gs_effect_create_from_file: Null 'file' parameter
gs_effect_create_from_file: Null 'file' parameter
gs_effect_create_from_file: Null 'file' parameter
gs_effect_create_from_file: Null 'file' parameter
gs_effect_create_from_file: Null 'file' parameter
gs_effect_create_from_file: Null 'file' parameter
gs_effect_create_from_file: Null 'file' parameter
gs_effect_create_from_file: Null 'file' parameter
gs_effect_create_from_file: Null 'file' parameter
OBS Studio works without problem. I tried reinstall video driver and run app with admin rights, but haven't success. Any ideas what can be wrong?