Trunk opens on its own (haunting?)

[driftingricegod]

Last night it did it for the first time ever. I was driving, pulled up to a red light, then i hear "pop" my trunk popped like when you press the TRUNK button on the key or when u press the latch before you lift the trunk glass.
I thought i was getting robbed or car jacked.
but then there was no one, i pulled over and needed to lift and shut the trunk (glass part)

Then it has done it 3 more times between last night and today. What I do now is that I make sure I lock my doors because it will lock the trunk glass.

What do you think the issue could be? have anyone seen it?
I think it could be something in the little rubber thing you press to lift the trunk.