Bias winding drops out.....dummy load on which rail?

[eem2am]

Hello,

I am doing a 43W isolated flyback
V(in) = 385V (=PFC Bus)
F(sw) = 67KHz
Burst Mode in standby

The outputs are 16V (2A6 max) and 5V8 (30mA max).
These secondaries are autotransformer wound.

In standby , it must draw less than 300mW from the mains.
(The PFC stage , and other stages are switched off in standby)

I am finding that the bias winding that supplies the Sanken STR2A155 PWM controller drops out if both 16V and 5V8 rails are completely unloaded.
-That is, the bias rail drops below 10V (from its normal 15V) and the PWM controller starts supplying itself from the HV rail via its internal linear regulator.

.....I notice that the bias winding comes back into regulation if the 5V8 rail is loaded with just 10mA.

....10mA corresponds to 58mW on the 5.8V rail.

Supposing i leave the 5V8 rail completely unloaded......
-and then put a load of 58mW on the 16V rail.....
-would you expect the bias winding to likewise come back into regulation?


.....or do you believe that the lower voltage winding (5.8V) is the best one to apply the dummy load to in order to keep the bias rail from dropping out?