Whats this noise? Vid inside

[Scoobykiller]

Hey all
Need some help
The second video is the note of the car engine on idle does it sound normal (byd)
The first video is when i rev the car and it give a slight rattle? Also does it when driving when i first press the accelerator?
What can it be?

https://vid.me/U1j7

https://vid.me/zLxH