The output generated for this file has a duration that is significantly longer than the input file's duration. Generally this is the result of invalid/inaccurate metadata or timestamps that cause the encoder to create a long file.
Three specific issues are common causes of this error: incorrect audio sample rate metadata, incorrect MP4/MOV edit list metadata, and bad timestamps.
Audio sample rate metadata may be incorrect, leading to interpreting the audio at half speed, doubling the duration of the file. This is not especially common, and we do our best to detect and fix these situations, but occasionally it happens.