Standby Problem

I put the Corebox pro into standby mode and the blue on/off switch starts flashing and keeps flashing. On screen it shows no signal so I presume it has gone into standby but why is the light flashing

I notice that several people have viewed my original post and over 200 responses across several topics. I presume all these people have a CoreBox Pro. Could some of you please tell me what happens when you switch to standby? Do you get a flashing light? Is this what is supposed to happen?
Any comments would be welcome.
Thannks