EMI problem w/ TNY284

I have a 4W design (2 isolated 15V 130mA outputs) integrated into a PFC + brushless motor drive and am doing prelim EMI testing.  I have fixed all areas that where above our limits except a 11.5MHz spike.  After disconnecting the PFC and  the motor drive, I stll have the problem freq. with the power supply lightly or fully loaded.  The only other switching on the board is a TPS6177 3.3V @ 70mA output buck converter switching at 1MHz and a uP (STM32F100C8T7 switching at 72MHz.  I have tried every trick I know to reduce this spike but nothing helps.  I have chg the layout on the power input side, tried  a PI filter on the input, and inductor on both + and - input, a common mode choke on the input, no inductor on the input, different combinations of "Y" caps.  When I "zoom" in on the problem spike w/ the spectrum analyzer, I see that it is composed of a series of  spikes 43.8KHz appart which appears to be the TNY284 switching freq / 3 and when I look at the D-S switching I see the freq changing varying from 16.2K to 48K to 66K Hz mostly.  I then looked at the D-S w/ a scope in FFT mode but didn't see anything around 11.5MHz.  I then looked at the main 15VDC output and did see a "bump" around 10.5MHz.

Any help in solving this would be greatly appreciated.