The issue has since been reported to IRremote for correction:
https://github.com/shirriff/Arduino-IRremote/issues/41
In summary, #define NEC_ONE_SPACE 1600 should be: #define NEC_ONE_SPACE 1692
(Actually, we use 1690 in AnaysIR, but what's 2 microseconds between friends [unless you are at the limit
![Very Happy :D](./images/smilies/icon_e_biggrin.gif)
It was a great validation of a tool like AnalysIR.