The situation is simple — on the website a couple of frames and a pair of blocks AdSence
the manifestation of the first — Reklama AdSense is displayed in another block of AdSense.
the second manifestation of ad is shown in my iframe, spoiling my parade :P
As such perhaps — I don't know, is relatively rare, every 10-20 F5.
Manifested at different sites.
Googling showed that I am not alone, nor any decision or justification problems are found