[FFmpeg-user] amix fills 16Gb memory, ffmpeg killed

[S Andreason]

Hi,
I am trying to join 11 video files, each 3 minutes in length. I can get 
the video rendered correctly, where the audio only lasts 3 minutes from 
input 0. But when I add the amix filter, it fills 16Gb of memory in 2 
minutes and gets it's process killed.

The full command line and output, before and after adding
;amix=inputs=11:duration=longest
are in this 43Kb text file:
https://www.seahorsecorral.org/videos/tests/ffmpeg-killed-16Gb-memory-full.txt

Is there a better way to write the command?
(without resorting to trimming each file, and then using concat filter.)
Thank you,
Stewart