What is this noise

[andererdoo]

Hello fellow GTIer!

I'm new on this forum and I just bought a 2012 Mk6 GTI CDM version (China assembled version, in case you guys wondering - it's EA888 produce slightly less hp than your European ver., 200hp to be accurate.)

I recently noticed a strange noise from the timing chain side of engine bay that I am not sure what it is.

Please refer to this video: https://imgur.com/a/euJ5JY6

There's a steady "burping" sound above the normal idling sound of engine.
Here is another video I found on youtube that has exactly the same noise as mine, for your reference: https://www.youtube.com/watch?v=EdE1MY-NKCM&list=LL&index=1

No EML or whatsoever now, the car runs smoothly but I just want to be cautious given the age and reputation of this engine.

Any help would be appreciated!!!