Rapid Long term A/D faulty on Due in 1.5.7

Somewhere between Ardunio 1.5.1 and 1.5.7 the Analog Read function has been changed and in 1.5.7 after about 5000 minutes of continuously reading the A/D inputs, the function will start failing and will readout either off scale or NaN values. This was not the case in version 1.5.1 and the same exact code compiled under 1.5.1 works perfectly.

The only other clue is that the speed at which the reads occur is much faster (roughly 80 hz vs 500 hz) for the software (which does a bunch of stuff in between reads) indicating that the Analog read function is much quicker now, but has a significant issue.