Maybe that won't help with the workaround but just to give a bit of background on why this is happening. We are using a library to do the parsing and evaluation of the expression. The round function is using something called 'rint' and citing the documentation ([1] and [2]):
"If two double values that are mathematical integers are equally close, the result is the integer value that is even." and "This has better statistical properties." (I am not sure what properties that are, though.)