I got a quick fix to that, and i do it because my ears are kind of small.
Firstly u straighten the whole cable.
Hold both piece of the iem, L and R respectively on each hands, turn both iems inwards 1 round then wear them.
It would create an inward bend that helps to prevent them from getting out behind ur ears when u wear them "over the ear"
Works for all cables, make 2 rounds if u feel it's not secure enuf.