OBS Encoding overloaded for seemingly no reason?

[MatteRB26]

So we started streaming a few weeks ago and everything was generally going fine. I was streaming & recording Phasmophobia on my PC at 1080p 60fps using a 2070 just fine (for a while) with a couple of Source Record filters running on the game and webcam.

After about 1.5-2hrs I'd start getting the Encoding overloaded! error in OBS, so I stopped the main recording and the error went away.

I noticed that our streams have became laggy running at 15-20 FPS on Twitch and OBS has the Encoding Overloaded! error all the time when streaming. I've been trying the Twitch test mode without even running a game and I get the same issue.

I tried Twitch test mode without even running a game this morning and the logs aren't at all helpful (https://obsproject.com/tools/analyzer?log_url=https://obsproject.com/logs/sxUzOpH9P3MCTdVG) and just tells me my GPU is overloaded, but it's not, and I used to stream & record at the same time.
Edit to add that I tried running OBS as admin as the logs suggest, which hasn't alleviated my issues.

While streaming Phasmophobia, my GPU 3D is sat around 80-90% and the Encode is sat around 60%, so barely overloaded...

For the stream output I'm using:
Video Bitrate: 6000kbps
Audio Bitrate: 160
Encoder: NVENC H.264
Encoder Preset: Medium

Task Manager with Phasmophobia running:

Any advice would be greatly appreciated as a 15 fps stream is abysmal

 

[MatteRB26]

So is it also lagging when you're just streaming, without recording?

Just to make sure, is Window's built in background recording disabled too? You can find it in Settings -> Gaming -> Captures.

Also lags with just streaming, yes and other recording is off, it used to be fine so I'm not sure why it's decided to do this now...

I tried StreamLabs, imported everything into there and that runs at all the same quality settings and is able to stream at 60FPS. Who knows what the hell I've done to OBS to upset it so much...