> try attached patch on top of 4 previous?

The V° patch is OK.
I remember to you that flac-1.3 result is:
** rendered 9063 frames in 0.646 secs, 14029.412 fps, size 18.2 MiB

flac-1.4

(0) : ** rendered 9063 frames in 4.124 secs, 2197.624 fps, size 18.1 MiB

(5) : ** rendered 9063 frames in 4.147 secs, 2185.435 fps, size 16.1 MiB

(8) : ** rendered 9063 frames in 12.901 secs, 702.504 fps, size 15.8 MiB

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