I have discovered a very nasty bug in Avidemux v2.5.x (it is present in v2.5.3 and v2.5.6)!
In essence: Avidemux does not check if there is enough free space on the destination drive when writing an output file, and will not react even after it fills the last free byte on the target drive - it will simply continue writing the output file to the destination drive, into God knows which sectors ....
Therefore, ALWAYS CHECK if the target drive for storing the output file from Avidemux has enough free space on it for the output file, and that its free space will not decrease in the meantime (for example, because your torrent program is filling it at the same time).
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