These kinds of incidents and errors look just like things programs written for Computer Science 101 classes would produce. This isn't some minor rounding error anymore - if true, someone has messed this up big time!
Have you seen the
BitGo integer overflow error? (BitGo gave to a lucky user a javascript tool to recover BTC from an old-format wallet. The tool had
an integer overflow bug that would send at most 2
32 - 1 satoshi (~40 BTC) to the destination output, leaving everything else as transaction fee. Fortunately the miner was nice and returned the ~80 BTC fee to the user.)