lsmas: failed to output a video frame.

[Selur]

Using "F:\Hybrid\64bit\Vapoursynth\vspipe.exe" "G:\Output\lsmash.vpy" g:\test.ypm --outputindex 0 -c y4m
with this script and the attached source

https://github.com/user-attachments/assets/7c76ea46-e30b-46fb-b20f-a79bfef30574
I get:

Error: Failed to retrieve frame 250 with error: lsmas: failed to output a video frame.
Output 282 frames in 0.24 seconds (1180.91 fps)

using LWLibavSource with this script (just the source filter changed) I get:

Output 5000 frames in 1.39 seconds (3594.85 fps)

I have this effect with multiple different sources. Whenever LSMASH source is used at some point I get "lsmas: failed to output a video frame."
I'm on Windows 11, using Vapoursynth VR72 using latest 20250706 1266.0.0.0.
Tested: LWLibavSource, BestSource, FFMS2, DGDecNV all work fine, only LibavSMASHSource fails.