cracks on wall near door

[Newby2]

My house is 16 years old. I just found there is a crack on the wall on top of the front door frame. It is along the line of the two walls meet, so sort of a straight line (not diagonal). It is not thick (<<1mm). The crack starts from a hole drilled by the previous owner (to pass some wire) on the wall near the door frame.
I am not sure how long the crack has been there. Could it be because of the hole drilled by the previous owner that results in the plaster crack? Or should I be concerned about it (sign of subsidence) as it is near the door?

Many thanks.

 

[roughcaster]

What are the walls made of?

Roughcaster.

 

[Newby2]

just usual wall of plaster board I guess.

 

[Newby2]

sorry, I knocked on different parts of the wall - from sound it seems that that the top corner (where the crack is) where the two walls meet is something different, sound thinner than a normal wall,ie more empty behind it. - don't know what it is.

 

[roughcaster]

It could be a plasterboard wall from what you say, but it could also be the hollow sound of loose plaster. Check the wall on the outside the front door and see if there is a crack in the same place. The cracked/hollow sounding plaster area of the wall, can easily be patched up, but either way, it doesn't sound much ,,, probably as a result of where the hole was drilled as you said,, i wouldn't think it was subsidence.

Roughcaster.