Here I am assuming that there is no problem with the electrical wiring.
This slight ‘shock’ is common in many TS STB’s, is due to a ‘half wave rectifier’ being used in the power circuit in the unit. This is a cheaper option, many circuit designers use. Better quality gadgets always use a ‘full wave rectifier’ in their circuits so users don’t face a ‘shock’. I had complained too as soon as it was installed & then later to their CC but the answer is the same ‘just ignore it’. :isleep:
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The transformer+rectifier is in adapter and not the stb

. The STB gets direct 12v dc direct. But the main point is that a rectifier has simply nothing to with it(avoiding technical jargon).
It just that the box is not properly insulated. Now by insulation don't confuse with earthing, low voltage dc devices almost never have earthing(moreover they have 2 pin supply ). They are actually given very high class plastic insulation which is more than enough to shield shocks.
In this case what i can infer is that the plastic used is of low quality which has resulted in this problem and hence 'CURRENT LEAKAGE'.
The best u could do is widespread old fashioned technique u can add secondary insulation by connecting a wire to the body of stb and then connect it to the ground/earth point in the socket. Of course do it only if u need it, like if u have kids in ur home, otherwise just don't touch it.
Some people have another problem too but i don't think its applicable here . People often complain abt getting a shock in spite of switches being off. This happens when the electric wiring is done in a wrong way and the 'switch' is connected to neutral instead of positive/live wire. Hence the device device remains at potential and leakage currents are formed.
:wewin: