This problem is mostly related with grounding. You can solve this problem if you change both multi-tap for PC and multi-tap for SMPS and adapter to grounding type. If grounding is unstable, the condition will be up in the air and the board will be unstable due to poor safe ground.

Therefore, make sure you use grounding multi-tap as the board can be broken if this case will be continued long. Sometimes houses built long ago or even apartments may not have safe ground treated properly.
In this case, it is recommended that you should request the safe ground works to use this product safely. If you feel computer sometime is just electrifying, you have to doubt what the problem is. That’s because this case is severe.

Thank you.