FP_SINCOS core bug

I am currently using the FP_SINCOS core and found some issues with the results. When configured as a cosine function it acts fine, however when It is configured to implement the sine function there are certain angles that do not produce the correct result.

Example: When I feed the core with angle 7pi/6(x"406A927F") or 210 degrees it will calculate -.25(x"BE800000") instead of -.5(x"BF000000), I have seen this only with certain angles only, making me think there is a bug with the internal LUTs.

Has anyone experienced this bug?

I have attached a simulation capture of the BUG