The very nature of a SMPS circuit is noise, so all SMPS's use line filters and one of these filters needs to be Earth Grounded.
If this filter is left floating the device it is powering will have half the mains AC voltage (~60Vac) plus the unfiltered switching noise on its DC/Chassis Ground...
When an ungrounded device is grounded by another devices connection to it, it is referred to as a "Vampire Connection", meaning it is not a good thing!
The rules for grounding a system are as follows:
1. Never connect a 2 pronged AC powered device to a 3 pronged AC powered device.
2. All...
Technically speaking the term "Ground Loop" is misused a lot in forums, a Ground Loop is a rare occurrence were a system has 2 Grounds from two different transformers, but in a house there is only 1 Ground!
Although, in circuit PCB designs and other sensitive electronics with multiple Ground...
To solve this issue you first have to confirm with an AC tester that all AC outlets being used are wired correctly.
The problem is that the TV/AVR are not grounded and the PC is! ( that's if the AC outlets are wired correctly).
This noise is usually a result of the AC polarity of one of the...