Hi all, any idea what could the squeaking noise come from in my mk7?

First thought was be the belt, but when I bought the car, the dealer assured me they've lubricated it enough so I suspect that it's be something else.

Here's the video of the sound:

the thing is that this sound appears quite intermittently - usually fades out after the car warms up. Also, I've noticed that when the sound is present, the car has noticeably less power (not sure if this is related to the issue at all)

i couldn't really hear any squeaking. stuff like this is so hard to tell when looking at the car in person and even then can be hard. my wife's focus was making a squeaking noise which would disappear when warmed up a bit. I just could not tell what is was. then one day travelling down the motorway all of the warning lights came on and the temp guage was at the top. I found the fan belt had come off (which also drives the water pump on a 2001 focus 1.6 petrol). the plastic tensioner wheel that tensions the fan belt had melted because the bearing on the pulley wheel had siezed. That is what had been making the squeaking noise. Car had done about 90k miles. RAC brought my car 100 miles back home on the back of a lorry.