UE 5.4.4 - Bad Performance - CPU and GPU idling, waiting for RHI thread

I’ve a super weird rendering issue that seemingly came with 5.4.4 (“hot fix”).

As you can see from the “UE Insights” screenshot, GPU and CPU are doing their job just fine, completing the frame as fast as possible, while the RHI thread idles a while (5.3ms) before it picks up.

Once the RHI thread is busy, CPU and GPU are almost done and then wait for a staggering 9ms, before moving on to the next frame.

This pretty much halfs the performance of my rendering.

Before 5.4.4, RHI, GPU and CPU (game) all started pretty much simultaneously and also came to an almost simultaneous end which, of course, is the desired behavior.

Has anyone seen something like this before or has any idea what I could do to counter this?

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