Voukoder drops frames

Hi!

I've a big project in UHD 29,97 and tried to export it with Voukoder R3 on an AMD 3900X with a RTX 2080 Super through NVENC H.264. Scaling is done in Adobe Media Encoder to 1920x1080, same Framerate. It is looking good, but as soon as Premiere renders its frames faster, Voukoder drops frames of the final file. The log says "Unable to write packet to disk." I cannot provide you the source files and try to dig down the problem. A x264 export works fine so it has to do with the NVENC core.

I'm encoding with advanced settings b_adapt=1 bf=4 gpu=0 preset=hq profile=high qp=20 rc=constqp rc-lookahead=64 spatial-aq=1 temporal-aq=1

This works flawless!

When adding b_ref_mode=middle it struggles and drops frames.

Do you have any idea, why it isn't working?

Here is one logfile of a short clip. Clip 00 Teaser v1.txt

This is the roughcut teaser of my project: Teaser (Without stuttering.)

It consists mostly of videoclips (graded through Premiere and Cuda) and at the end is a graphicanimation dynamic-linked out of After Effects. This part takes longer to render and Voukoder doesn't drop frames anymore.

Maybe you have an idea, maybe I'm using it wrong...

I've tried the b_ref_mode=middle with another project and the same same error and message is visible in the log.

Choosing drive C: instead of E: doesn't change the output or log-messages.

C is a NVMe SSD and E consists of 4 SATA-SSDs in RAID-0

My system has 64GB of RAM and its not saturated during these exports.

If you have any ideas or things I can test for you, just ask. It's frustrating, but not super necessary.