Program Soraka Invisible Silence

I was laning a against a Program Soraka and when she uses her silence i couldnt see it but i can hear it and the silence stats shows. After that i paid close attention to her when she silences and it doesnt happen all the time but i think it happens when she use it near/in walls it disappear. If anyone owns this skin could you test it out to see if that what really cause it.