Transmission whirling sound

[Fungus007]

I have a 2014 1.33l 6 speed iq. 

Whenever I accelerate in any gear between 80-85kmh in any gear I can hear this faint whirling sound coming from the centre console which I’m guessing is where the transmission is. Outside the aforementioned speed no noise can be heard. 

I’ve ruled out a bad wheel bearings cos the sound goes away as soon as I put the car in neutral and let the car coast or depress the clutch. 
 

I got my mechanic to take it for a test drive and he said it was perfect fine. He said he could even hear the noise but at a different frequency below 80kmh but it so happens the frequency I can only detect is at 80-85km/h. 
 

I don’t really believe this cos I know the age impacts on what frequently a human can hear and cos I’m in my 30s i could think a large majority of iq owners would fall within this age group yet I don’t hear any complaints. 
 

I’ve been trying to self diagnose the issue and came across this video where they show a noise of a car with bad pinion gears which so happens to be exactly the same whirl I hear on my iq. 

https://youtu.be/Awbk1kPydX4?si=SuaQQmyeM3ilBsOG

Although not an iq this car makes a similar whirling sound 

https://youtu.be/Uayr9nREpFM?si=6xQYY4YVe4EMZ_Iy